configure.html revision 1.1.1.20
1 1.1.1.14 mrg <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 2 1.1.1.14 mrg <html> 3 1.1.1.20 mrg <!-- Created by GNU Texinfo 6.8, https://www.gnu.org/software/texinfo/ --> 4 1.1.1.20 mrg <head> 5 1.1.1.20 mrg <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> 6 1.1.1.19 mrg <!-- Copyright (C) 1988-2022 Free Software Foundation, Inc. 7 1.1 mrg 8 1.1.1.14 mrg Permission is granted to copy, distribute and/or modify this document 9 1.1.1.3 skrll under the terms of the GNU Free Documentation License, Version 1.3 or 10 1.1 mrg any later version published by the Free Software Foundation; with no 11 1.1 mrg Invariant Sections, the Front-Cover texts being (a) (see below), and 12 1.1 mrg with the Back-Cover Texts being (b) (see below). 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Copies published by the Free Software Foundation raise 24 1.1.1.14 mrg funds for GNU development. --> 25 1.1.1.16 mrg <title>Installing GCC: Configuration</title> 26 1.1.1.14 mrg 27 1.1.1.16 mrg <meta name="description" content="Installing GCC: Configuration"> 28 1.1.1.16 mrg <meta name="keywords" content="Installing GCC: Configuration"> 29 1.1.1.14 mrg <meta name="resource-type" content="document"> 30 1.1.1.14 mrg <meta name="distribution" content="global"> 31 1.1.1.14 mrg <meta name="Generator" content="makeinfo"> 32 1.1.1.20 mrg <meta name="viewport" content="width=device-width,initial-scale=1"> 33 1.1.1.20 mrg 34 1.1.1.14 mrg <style type="text/css"> 35 1.1.1.14 mrg <!-- 36 1.1.1.20 mrg a.copiable-anchor {visibility: hidden; text-decoration: none; line-height: 0em} 37 1.1.1.14 mrg a.summary-letter {text-decoration: none} 38 1.1.1.14 mrg blockquote.indentedblock {margin-right: 0em} 39 1.1.1.14 mrg div.display {margin-left: 3.2em} 40 1.1.1.14 mrg div.example {margin-left: 3.2em} 41 1.1.1.14 mrg kbd {font-style: oblique} 42 1.1.1.14 mrg pre.display {font-family: inherit} 43 1.1.1.14 mrg pre.format {font-family: inherit} 44 1.1.1.14 mrg pre.menu-comment {font-family: serif} 45 1.1.1.14 mrg pre.menu-preformatted {font-family: serif} 46 1.1.1.14 mrg span.nolinebreak {white-space: nowrap} 47 1.1.1.14 mrg span.roman {font-family: initial; font-weight: normal} 48 1.1.1.14 mrg span.sansserif {font-family: sans-serif; font-weight: normal} 49 1.1.1.20 mrg span:hover a.copiable-anchor {visibility: visible} 50 1.1.1.14 mrg ul.no-bullet {list-style: none} 51 1.1.1.14 mrg --> 52 1.1.1.14 mrg </style> 53 1.1.1.14 mrg 54 1.1.1.14 mrg 55 1.1 mrg </head> 56 1.1.1.13 mrg 57 1.1.1.14 mrg <body lang="en"> 58 1.1.1.16 mrg <h1 class="settitle" align="center">Installing GCC: Configuration</h1> 59 1.1.1.14 mrg 60 1.1.1.14 mrg 61 1.1.1.14 mrg 62 1.1.1.14 mrg 63 1.1.1.14 mrg 64 1.1.1.14 mrg 65 1.1.1.13 mrg 66 1.1.1.13 mrg 67 1.1.1.14 mrg 68 1.1.1.14 mrg 69 1.1.1.14 mrg 70 1.1.1.14 mrg 71 1.1.1.14 mrg 72 1.1.1.14 mrg 73 1.1.1.14 mrg 74 1.1.1.14 mrg 75 1.1.1.14 mrg 76 1.1.1.14 mrg 77 1.1.1.14 mrg 78 1.1.1.20 mrg <span id="index-Configuration"></span> 79 1.1.1.20 mrg <span id="index-Installing-GCC_003a-Configuration"></span> 80 1.1.1.14 mrg 81 1.1.1.14 mrg <p>Like most GNU software, GCC must be configured before it can be built. 82 1.1.1.14 mrg This document describes the recommended configuration procedure 83 1.1.1.14 mrg for both native and cross targets. 84 1.1.1.14 mrg </p> 85 1.1.1.14 mrg <p>We use <var>srcdir</var> to refer to the toplevel source directory for 86 1.1.1.14 mrg GCC; we use <var>objdir</var> to refer to the toplevel build/object directory. 87 1.1.1.14 mrg </p> 88 1.1.1.14 mrg <p>If you obtained the sources by cloning the repository, <var>srcdir</var> 89 1.1.1.14 mrg must refer to the top <samp>gcc</samp> directory, the one where the 90 1.1.1.14 mrg <samp>MAINTAINERS</samp> file can be found, and not its <samp>gcc</samp> 91 1.1.1.14 mrg subdirectory, otherwise the build will fail. 92 1.1.1.14 mrg </p> 93 1.1.1.14 mrg <p>If either <var>srcdir</var> or <var>objdir</var> is located on an automounted NFS 94 1.1.1.14 mrg file system, the shell’s built-in <code>pwd</code> command will return 95 1.1 mrg temporary pathnames. Using these can lead to various sorts of build 96 1.1.1.14 mrg problems. To avoid this issue, set the <code>PWDCMD</code> environment 97 1.1.1.14 mrg variable to an automounter-aware <code>pwd</code> command, e.g., 98 1.1.1.14 mrg <code>pawd</code> or ‘<samp>amq -w</samp>’, during the configuration and build 99 1.1 mrg phases. 100 1.1.1.14 mrg </p> 101 1.1.1.14 mrg <p>First, we <strong>highly</strong> recommend that GCC be built into a 102 1.1 mrg separate directory from the sources which does <strong>not</strong> reside 103 1.1 mrg within the source tree. This is how we generally build GCC; building 104 1.1.1.14 mrg where <var>srcdir</var> == <var>objdir</var> should still work, but doesn’t 105 1.1 mrg get extensive testing; building where <var>objdir</var> is a subdirectory 106 1.1 mrg of <var>srcdir</var> is unsupported. 107 1.1.1.14 mrg </p> 108 1.1.1.14 mrg <p>If you have previously built GCC in the same directory for a 109 1.1.1.14 mrg different target machine, do ‘<samp>make distclean</samp>’ to delete all files 110 1.1.1.14 mrg that might be invalid. One of the files this deletes is <samp>Makefile</samp>; 111 1.1.1.14 mrg if ‘<samp>make distclean</samp>’ complains that <samp>Makefile</samp> does not exist 112 1.1.1.14 mrg or issues a message like “don’t know how to make distclean” it probably 113 1.1 mrg means that the directory is already suitably clean. However, with the 114 1.1 mrg recommended method of building in a separate <var>objdir</var>, you should 115 1.1 mrg simply use a different <var>objdir</var> for each target. 116 1.1.1.14 mrg </p> 117 1.1.1.14 mrg <p>Second, when configuring a native system, either <code>cc</code> or 118 1.1.1.14 mrg <code>gcc</code> must be in your path or you must set <code>CC</code> in 119 1.1 mrg your environment before running configure. Otherwise the configuration 120 1.1 mrg scripts may fail. 121 1.1.1.14 mrg </p> 122 1.1 mrg 123 1.1.1.14 mrg <p>To configure GCC: 124 1.1.1.14 mrg </p> 125 1.1.1.20 mrg <div class="example"> 126 1.1.1.20 mrg <pre class="example">% mkdir <var>objdir</var> 127 1.1.1.14 mrg % cd <var>objdir</var> 128 1.1.1.14 mrg % <var>srcdir</var>/configure [<var>options</var>] [<var>target</var>] 129 1.1.1.14 mrg </pre></div> 130 1.1 mrg 131 1.1.1.20 mrg <span id="Distributor-options"></span><h3 class="heading">Distributor options</h3> 132 1.1 mrg 133 1.1 mrg <p>If you will be distributing binary versions of GCC, with modifications 134 1.1 mrg to the source code, you should use the options described in this 135 1.1 mrg section to make clear that your version contains modifications. 136 1.1.1.14 mrg </p> 137 1.1.1.14 mrg <dl compact="compact"> 138 1.1.1.20 mrg <dt><span><code>--with-pkgversion=<var>version</var></code></span></dt> 139 1.1.1.14 mrg <dd><p>Specify a string that identifies your package. You may wish 140 1.1 mrg to include a build number or build date. This version string will be 141 1.1.1.14 mrg included in the output of <code>gcc --version</code>. This suffix does 142 1.1.1.14 mrg not replace the default version string, only the ‘<samp>GCC</samp>’ part. 143 1.1.1.14 mrg </p> 144 1.1.1.14 mrg <p>The default value is ‘<samp>GCC</samp>’. 145 1.1.1.14 mrg </p> 146 1.1.1.14 mrg </dd> 147 1.1.1.20 mrg <dt><span><code>--with-bugurl=<var>url</var></code></span></dt> 148 1.1.1.14 mrg <dd><p>Specify the URL that users should visit if they wish to report a bug. 149 1.1 mrg You are of course welcome to forward bugs reported to you to the FSF, 150 1.1 mrg if you determine that they are not bugs in your modifications. 151 1.1.1.14 mrg </p> 152 1.1.1.14 mrg <p>The default value refers to the FSF’s GCC bug tracker. 153 1.1.1.14 mrg </p> 154 1.1.1.14 mrg </dd> 155 1.1.1.20 mrg <dt><span><code>--with-documentation-root-url=<var>url</var></code></span></dt> 156 1.1.1.16 mrg <dd><p>Specify the URL root that contains GCC option documentation. The <var>url</var> 157 1.1.1.16 mrg should end with a <code>/</code> character. 158 1.1.1.16 mrg </p> 159 1.1.1.16 mrg <p>The default value is <a href="https://gcc.gnu.org/onlinedocs/">https://gcc.gnu.org/onlinedocs/</a>. 160 1.1.1.16 mrg </p> 161 1.1.1.16 mrg </dd> 162 1.1.1.20 mrg <dt><span><code>--with-changes-root-url=<var>url</var></code></span></dt> 163 1.1.1.16 mrg <dd><p>Specify the URL root that contains information about changes in GCC 164 1.1.1.16 mrg releases like <code>gcc-<var>version</var>/changes.html</code>. 165 1.1.1.16 mrg The <var>url</var> should end with a <code>/</code> character. 166 1.1.1.16 mrg </p> 167 1.1.1.16 mrg <p>The default value is <a href="https://gcc.gnu.org/">https://gcc.gnu.org/</a>. 168 1.1.1.16 mrg </p> 169 1.1.1.16 mrg </dd> 170 1.1.1.14 mrg </dl> 171 1.1 mrg 172 1.1.1.20 mrg <span id="Host_002c-Build-and-Target-specification"></span><h3 class="heading">Host, Build and Target specification</h3> 173 1.1 mrg 174 1.1.1.19 mrg <p>Specify the host, build and target machine configurations. You do this 175 1.1.1.19 mrg when you run the <samp>configure</samp> script. 176 1.1.1.19 mrg </p> 177 1.1.1.19 mrg <p>The <em>build</em> machine is the system which you are using, the 178 1.1.1.19 mrg <em>host</em> machine is the system where you want to run the resulting 179 1.1.1.19 mrg compiler (normally the build machine), and the <em>target</em> machine is 180 1.1.1.19 mrg the system for which you want the compiler to generate code. 181 1.1.1.19 mrg </p> 182 1.1.1.19 mrg <p>If you are building a compiler to produce code for the machine it runs 183 1.1.1.19 mrg on (a native compiler), you normally do not need to specify any operands 184 1.1.1.19 mrg to <samp>configure</samp>; it will try to guess the type of machine you are on 185 1.1.1.19 mrg and use that as the build, host and target machines. So you don’t need 186 1.1.1.19 mrg to specify a configuration when building a native compiler unless 187 1.1.1.19 mrg <samp>configure</samp> cannot figure out what your configuration is or guesses 188 1.1.1.19 mrg wrong. 189 1.1.1.19 mrg </p> 190 1.1.1.19 mrg <p>In those cases, specify the build machine’s <em>configuration name</em> 191 1.1.1.19 mrg with the <samp>--host</samp> option; the host and target will default to be 192 1.1.1.19 mrg the same as the host machine. 193 1.1.1.19 mrg </p> 194 1.1.1.19 mrg <p>Here is an example: 195 1.1.1.19 mrg </p> 196 1.1.1.20 mrg <div class="example"> 197 1.1.1.20 mrg <pre class="example">./configure --host=x86_64-pc-linux-gnu 198 1.1.1.19 mrg </pre></div> 199 1.1.1.11 mrg 200 1.1.1.19 mrg <p>A configuration name may be canonical or it may be more or less 201 1.1.1.19 mrg abbreviated (<samp>config.sub</samp> script produces canonical versions). 202 1.1.1.19 mrg </p> 203 1.1.1.19 mrg <p>A canonical configuration name has three parts, separated by dashes. 204 1.1.1.19 mrg It looks like this: ‘<samp><var>cpu</var>-<var>company</var>-<var>system</var></samp>’. 205 1.1.1.19 mrg </p> 206 1.1.1.19 mrg <p>Here are the possible CPU types: 207 1.1.1.19 mrg </p> 208 1.1.1.19 mrg <blockquote> 209 1.1.1.19 mrg <p>aarch64, aarch64_be, alpha, alpha64, amdgcn, arc, arceb, arm, armeb, avr, bfin, 210 1.1.1.19 mrg bpf, cr16, cris, csky, epiphany, fido, fr30, frv, ft32, h8300, hppa, hppa2.0, 211 1.1.1.19 mrg hppa64, i486, i686, ia64, iq2000, lm32, loongarch64, m32c, m32r, m32rle, m68k, 212 1.1.1.19 mrg mcore, microblaze, microblazeel, mips, mips64, mips64el, mips64octeon, 213 1.1.1.19 mrg mips64orion, mips64vr, mipsel, mipsisa32, mipsisa32r2, mipsisa64, mipsisa64r2, 214 1.1.1.19 mrg mipsisa64r2el, mipsisa64sb1, mipsisa64sr71k, mipstx39, mmix, mn10300, moxie, 215 1.1.1.19 mrg msp430, nds32be, nds32le, nios2, nvptx, or1k, pdp11, powerpc, powerpc64, 216 1.1.1.19 mrg powerpc64le, powerpcle, pru, riscv32, riscv32be, riscv64, riscv64be, rl78, rx, 217 1.1.1.19 mrg s390, s390x, sh, shle, sparc, sparc64, tic6x, tilegx, tilegxbe, tilepro, v850, 218 1.1.1.19 mrg v850e, v850e1, vax, visium, x86_64, xstormy16, xtensa 219 1.1.1.19 mrg </p></blockquote> 220 1.1.1.19 mrg 221 1.1.1.19 mrg <p>Here is a list of system types: 222 1.1.1.19 mrg </p> 223 1.1.1.19 mrg <blockquote> 224 1.1.1.19 mrg <p>aix<var>version</var>, amdhsa, aout, cygwin, darwin<var>version</var>, 225 1.1.1.19 mrg eabi, eabialtivec, eabisim, eabisimaltivec, elf, elf32, 226 1.1.1.19 mrg elfbare, elfoabi, freebsd<var>version</var>, gnu, hpux, hpux<var>version</var>, 227 1.1.1.19 mrg kfreebsd-gnu, kopensolaris-gnu, linux-androideabi, linux-gnu, 228 1.1.1.19 mrg linux-gnu_altivec, linux-musl, linux-uclibc, lynxos, mingw32, mingw32crt, 229 1.1.1.19 mrg mmixware, msdosdjgpp, netbsd, netbsdelf<var>version</var>, nto-qnx, openbsd, 230 1.1.1.19 mrg rtems, solaris<var>version</var>, symbianelf, tpf, uclinux, uclinux_eabi, vms, 231 1.1.1.19 mrg vxworks, vxworksae, vxworksmils 232 1.1.1.19 mrg </p></blockquote> 233 1.1.1.14 mrg 234 1.1.1.20 mrg <span id="Options-specification"></span><h3 class="heading">Options specification</h3> 235 1.1 mrg 236 1.1 mrg <p>Use <var>options</var> to override several configure time options for 237 1.1.1.14 mrg GCC. A list of supported <var>options</var> follows; ‘<samp>configure 238 1.1.1.14 mrg --help</samp>’ may list other options, but those not listed below may not 239 1.1 mrg work and should not normally be used. 240 1.1.1.14 mrg </p> 241 1.1.1.14 mrg <p>Note that each <samp>--enable</samp> option has a corresponding 242 1.1.1.14 mrg <samp>--disable</samp> option and that each <samp>--with</samp> option has a 243 1.1.1.14 mrg corresponding <samp>--without</samp> option. 244 1.1.1.14 mrg </p> 245 1.1.1.14 mrg <dl compact="compact"> 246 1.1.1.20 mrg <dt><span><code>--prefix=<var>dirname</var></code></span></dt> 247 1.1.1.14 mrg <dd><p>Specify the toplevel installation 248 1.1 mrg directory. This is the recommended way to install the tools into a directory 249 1.1 mrg other than the default. The toplevel installation directory defaults to 250 1.1.1.14 mrg <samp>/usr/local</samp>. 251 1.1.1.14 mrg </p> 252 1.1.1.14 mrg <p>We <strong>highly</strong> recommend against <var>dirname</var> being the same or a 253 1.1 mrg subdirectory of <var>objdir</var> or vice versa. If specifying a directory 254 1.1.1.14 mrg beneath a user’s home directory tree, some shells will not expand 255 1.1.1.14 mrg <var>dirname</var> correctly if it contains the ‘<samp>~</samp>’ metacharacter; use 256 1.1.1.14 mrg <code>$HOME</code> instead. 257 1.1.1.14 mrg </p> 258 1.1.1.14 mrg <p>The following standard <code>autoconf</code> options are supported. Normally you 259 1.1 mrg should not need to use these options. 260 1.1.1.14 mrg </p><dl compact="compact"> 261 1.1.1.20 mrg <dt><span><code>--exec-prefix=<var>dirname</var></code></span></dt> 262 1.1.1.14 mrg <dd><p>Specify the toplevel installation directory for architecture-dependent 263 1.1 mrg files. The default is <samp><var>prefix</var></samp>. 264 1.1.1.14 mrg </p> 265 1.1.1.14 mrg </dd> 266 1.1.1.20 mrg <dt><span><code>--bindir=<var>dirname</var></code></span></dt> 267 1.1.1.14 mrg <dd><p>Specify the installation directory for the executables called by users 268 1.1.1.14 mrg (such as <code>gcc</code> and <code>g++</code>). The default is 269 1.1.1.14 mrg <samp><var>exec-prefix</var>/bin</samp>. 270 1.1.1.14 mrg </p> 271 1.1.1.14 mrg </dd> 272 1.1.1.20 mrg <dt><span><code>--libdir=<var>dirname</var></code></span></dt> 273 1.1.1.14 mrg <dd><p>Specify the installation directory for object code libraries and 274 1.1.1.14 mrg internal data files of GCC. The default is <samp><var>exec-prefix</var>/lib</samp>. 275 1.1.1.14 mrg </p> 276 1.1.1.14 mrg </dd> 277 1.1.1.20 mrg <dt><span><code>--libexecdir=<var>dirname</var></code></span></dt> 278 1.1.1.14 mrg <dd><p>Specify the installation directory for internal executables of GCC. 279 1.1.1.14 mrg The default is <samp><var>exec-prefix</var>/libexec</samp>. 280 1.1.1.14 mrg </p> 281 1.1.1.14 mrg </dd> 282 1.1.1.20 mrg <dt><span><code>--with-slibdir=<var>dirname</var></code></span></dt> 283 1.1.1.14 mrg <dd><p>Specify the installation directory for the shared libgcc library. The 284 1.1 mrg default is <samp><var>libdir</var></samp>. 285 1.1.1.14 mrg </p> 286 1.1.1.14 mrg </dd> 287 1.1.1.20 mrg <dt><span><code>--datarootdir=<var>dirname</var></code></span></dt> 288 1.1.1.14 mrg <dd><p>Specify the root of the directory tree for read-only architecture-independent 289 1.1.1.14 mrg data files referenced by GCC. The default is <samp><var>prefix</var>/share</samp>. 290 1.1.1.14 mrg </p> 291 1.1.1.14 mrg </dd> 292 1.1.1.20 mrg <dt><span><code>--infodir=<var>dirname</var></code></span></dt> 293 1.1.1.14 mrg <dd><p>Specify the installation directory for documentation in info format. 294 1.1.1.14 mrg The default is <samp><var>datarootdir</var>/info</samp>. 295 1.1.1.14 mrg </p> 296 1.1.1.14 mrg </dd> 297 1.1.1.20 mrg <dt><span><code>--datadir=<var>dirname</var></code></span></dt> 298 1.1.1.14 mrg <dd><p>Specify the installation directory for some architecture-independent 299 1.1 mrg data files referenced by GCC. The default is <samp><var>datarootdir</var></samp>. 300 1.1.1.14 mrg </p> 301 1.1.1.14 mrg </dd> 302 1.1.1.20 mrg <dt><span><code>--docdir=<var>dirname</var></code></span></dt> 303 1.1.1.14 mrg <dd><p>Specify the installation directory for documentation files (other 304 1.1.1.14 mrg than Info) for GCC. The default is <samp><var>datarootdir</var>/doc</samp>. 305 1.1.1.14 mrg </p> 306 1.1.1.14 mrg </dd> 307 1.1.1.20 mrg <dt><span><code>--htmldir=<var>dirname</var></code></span></dt> 308 1.1.1.14 mrg <dd><p>Specify the installation directory for HTML documentation files. 309 1.1 mrg The default is <samp><var>docdir</var></samp>. 310 1.1.1.14 mrg </p> 311 1.1.1.14 mrg </dd> 312 1.1.1.20 mrg <dt><span><code>--pdfdir=<var>dirname</var></code></span></dt> 313 1.1.1.14 mrg <dd><p>Specify the installation directory for PDF documentation files. 314 1.1 mrg The default is <samp><var>docdir</var></samp>. 315 1.1.1.14 mrg </p> 316 1.1.1.14 mrg </dd> 317 1.1.1.20 mrg <dt><span><code>--mandir=<var>dirname</var></code></span></dt> 318 1.1.1.14 mrg <dd><p>Specify the installation directory for manual pages. The default is 319 1.1.1.14 mrg <samp><var>datarootdir</var>/man</samp>. (Note that the manual pages are only extracts 320 1.1 mrg from the full GCC manuals, which are provided in Texinfo format. The manpages 321 1.1 mrg are derived by an automatic conversion process from parts of the full 322 1.1 mrg manual.) 323 1.1.1.14 mrg </p> 324 1.1.1.14 mrg </dd> 325 1.1.1.20 mrg <dt><span><code>--with-gxx-include-dir=<var>dirname</var></code></span></dt> 326 1.1.1.14 mrg <dd><p>Specify 327 1.1 mrg the installation directory for G++ header files. The default depends 328 1.1 mrg on other configuration options, and differs between cross and native 329 1.1 mrg configurations. 330 1.1.1.14 mrg </p> 331 1.1.1.14 mrg </dd> 332 1.1.1.20 mrg <dt><span><code>--with-specs=<var>specs</var></code></span></dt> 333 1.1.1.14 mrg <dd><p>Specify additional command line driver SPECS. 334 1.1.1.3 skrll This can be useful if you need to turn on a non-standard feature by 335 1.1.1.14 mrg default without modifying the compiler’s source code, for instance 336 1.1.1.14 mrg <samp>--with-specs=%{!fcommon:%{!fno-common:-fno-common}}</samp>. 337 1.1.1.3 skrll See “Spec Files” in the main manual 338 1.1.1.14 mrg </p> 339 1.1.1.14 mrg </dd> 340 1.1.1.14 mrg </dl> 341 1.1.1.3 skrll 342 1.1.1.14 mrg </dd> 343 1.1.1.20 mrg <dt><span><code>--program-prefix=<var>prefix</var></code></span></dt> 344 1.1.1.14 mrg <dd><p>GCC supports some transformations of the names of its programs when 345 1.1 mrg installing them. This option prepends <var>prefix</var> to the names of 346 1.1 mrg programs to install in <var>bindir</var> (see above). For example, specifying 347 1.1.1.14 mrg <samp>--program-prefix=foo-</samp> would result in ‘<samp>gcc</samp>’ 348 1.1.1.14 mrg being installed as <samp>/usr/local/bin/foo-gcc</samp>. 349 1.1.1.14 mrg </p> 350 1.1.1.14 mrg </dd> 351 1.1.1.20 mrg <dt><span><code>--program-suffix=<var>suffix</var></code></span></dt> 352 1.1.1.14 mrg <dd><p>Appends <var>suffix</var> to the names of programs to install in <var>bindir</var> 353 1.1.1.14 mrg (see above). For example, specifying <samp>--program-suffix=-3.1</samp> 354 1.1.1.14 mrg would result in ‘<samp>gcc</samp>’ being installed as 355 1.1.1.14 mrg <samp>/usr/local/bin/gcc-3.1</samp>. 356 1.1.1.14 mrg </p> 357 1.1.1.14 mrg </dd> 358 1.1.1.20 mrg <dt><span><code>--program-transform-name=<var>pattern</var></code></span></dt> 359 1.1.1.14 mrg <dd><p>Applies the ‘<samp>sed</samp>’ script <var>pattern</var> to be applied to the names 360 1.1 mrg of programs to install in <var>bindir</var> (see above). <var>pattern</var> has to 361 1.1.1.14 mrg consist of one or more basic ‘<samp>sed</samp>’ editing commands, separated by 362 1.1.1.14 mrg semicolons. For example, if you want the ‘<samp>gcc</samp>’ program name to be 363 1.1.1.14 mrg transformed to the installed program <samp>/usr/local/bin/myowngcc</samp> and 364 1.1.1.14 mrg the ‘<samp>g++</samp>’ program name to be transformed to 365 1.1.1.14 mrg <samp>/usr/local/bin/gspecial++</samp> without changing other program names, 366 1.1 mrg you could use the pattern 367 1.1.1.14 mrg <samp>--program-transform-name='s/^gcc$/myowngcc/; s/^g++$/gspecial++/'</samp> 368 1.1 mrg to achieve this effect. 369 1.1.1.14 mrg </p> 370 1.1.1.14 mrg <p>All three options can be combined and used together, resulting in more 371 1.1 mrg complex conversion patterns. As a basic rule, <var>prefix</var> (and 372 1.1 mrg <var>suffix</var>) are prepended (appended) before further transformations 373 1.1 mrg can happen with a special transformation script <var>pattern</var>. 374 1.1.1.14 mrg </p> 375 1.1.1.14 mrg <p>As currently implemented, this option only takes effect for native 376 1.1.1.14 mrg builds; cross compiler binaries’ names are not transformed even when a 377 1.1 mrg transformation is explicitly asked for by one of these options. 378 1.1.1.14 mrg </p> 379 1.1.1.14 mrg <p>For native builds, some of the installed programs are also installed 380 1.1 mrg with the target alias in front of their name, as in 381 1.1.1.14 mrg ‘<samp>i686-pc-linux-gnu-gcc</samp>’. All of the above transformations happen 382 1.1 mrg before the target alias is prepended to the name—so, specifying 383 1.1.1.14 mrg <samp>--program-prefix=foo-</samp> and <samp>program-suffix=-3.1</samp>, the 384 1.1 mrg resulting binary would be installed as 385 1.1.1.14 mrg <samp>/usr/local/bin/i686-pc-linux-gnu-foo-gcc-3.1</samp>. 386 1.1.1.14 mrg </p> 387 1.1.1.14 mrg <p>As a last shortcoming, none of the installed Ada programs are 388 1.1 mrg transformed yet, which will be fixed in some time. 389 1.1.1.14 mrg </p> 390 1.1.1.14 mrg </dd> 391 1.1.1.20 mrg <dt><span><code>--with-local-prefix=<var>dirname</var></code></span></dt> 392 1.1.1.14 mrg <dd><p>Specify the 393 1.1 mrg installation directory for local include files. The default is 394 1.1.1.14 mrg <samp>/usr/local</samp>. Specify this option if you want the compiler to 395 1.1.1.14 mrg search directory <samp><var>dirname</var>/include</samp> for locally installed 396 1.1.1.14 mrg header files <em>instead</em> of <samp>/usr/local/include</samp>. 397 1.1.1.14 mrg </p> 398 1.1.1.14 mrg <p>You should specify <samp>--with-local-prefix</samp> <strong>only</strong> if your 399 1.1.1.14 mrg site has a different convention (not <samp>/usr/local</samp>) for where to put 400 1.1 mrg site-specific files. 401 1.1.1.14 mrg </p> 402 1.1.1.14 mrg <p>The default value for <samp>--with-local-prefix</samp> is <samp>/usr/local</samp> 403 1.1.1.14 mrg regardless of the value of <samp>--prefix</samp>. Specifying 404 1.1.1.14 mrg <samp>--prefix</samp> has no effect on which directory GCC searches for 405 1.1 mrg local header files. This may seem counterintuitive, but actually it is 406 1.1 mrg logical. 407 1.1.1.14 mrg </p> 408 1.1.1.14 mrg <p>The purpose of <samp>--prefix</samp> is to specify where to <em>install 409 1.1.1.14 mrg GCC</em>. The local header files in <samp>/usr/local/include</samp>—if you put 410 1.1 mrg any in that directory—are not part of GCC. They are part of other 411 1.1 mrg programs—perhaps many others. (GCC installs its own header files in 412 1.1.1.14 mrg another directory which is based on the <samp>--prefix</samp> value.) 413 1.1.1.14 mrg </p> 414 1.1.1.14 mrg <p>Both the local-prefix include directory and the GCC-prefix include 415 1.1.1.14 mrg directory are part of GCC’s “system include” directories. Although these 416 1.1 mrg two directories are not fixed, they need to be searched in the proper 417 1.1 mrg order for the correct processing of the include_next directive. The 418 1.1 mrg local-prefix include directory is searched before the GCC-prefix 419 1.1 mrg include directory. Another characteristic of system include directories 420 1.1 mrg is that pedantic warnings are turned off for headers in these directories. 421 1.1.1.14 mrg </p> 422 1.1.1.14 mrg <p>Some autoconf macros add <samp>-I <var>directory</var></samp> options to the 423 1.1 mrg compiler command line, to ensure that directories containing installed 424 1.1.1.14 mrg packages’ headers are searched. When <var>directory</var> is one of GCC’s 425 1.1 mrg system include directories, GCC will ignore the option so that system 426 1.1 mrg directories continue to be processed in the correct order. This 427 1.1 mrg may result in a search order different from what was specified but the 428 1.1 mrg directory will still be searched. 429 1.1.1.14 mrg </p> 430 1.1.1.14 mrg <p>GCC automatically searches for ordinary libraries using 431 1.1.1.14 mrg <code>GCC_EXEC_PREFIX</code>. Thus, when the same installation prefix is 432 1.1 mrg used for both GCC and packages, GCC will automatically search for 433 1.1 mrg both headers and libraries. This provides a configuration that is 434 1.1 mrg easy to use. GCC behaves in a manner similar to that when it is 435 1.1.1.14 mrg installed as a system compiler in <samp>/usr</samp>. 436 1.1.1.14 mrg </p> 437 1.1.1.14 mrg <p>Sites that need to install multiple versions of GCC may not want to 438 1.1 mrg use the above simple configuration. It is possible to use the 439 1.1.1.14 mrg <samp>--program-prefix</samp>, <samp>--program-suffix</samp> and 440 1.1.1.14 mrg <samp>--program-transform-name</samp> options to install multiple versions 441 1.1 mrg into a single directory, but it may be simpler to use different prefixes 442 1.1.1.14 mrg and the <samp>--with-local-prefix</samp> option to specify the location of the 443 1.1 mrg site-specific files for each version. It will then be necessary for 444 1.1 mrg users to specify explicitly the location of local site libraries 445 1.1.1.14 mrg (e.g., with <code>LIBRARY_PATH</code>). 446 1.1.1.14 mrg </p> 447 1.1.1.14 mrg <p>The same value can be used for both <samp>--with-local-prefix</samp> and 448 1.1.1.14 mrg <samp>--prefix</samp> provided it is not <samp>/usr</samp>. This can be used 449 1.1.1.14 mrg to avoid the default search of <samp>/usr/local/include</samp>. 450 1.1.1.14 mrg </p> 451 1.1.1.14 mrg <p><strong>Do not</strong> specify <samp>/usr</samp> as the <samp>--with-local-prefix</samp>! 452 1.1.1.14 mrg The directory you use for <samp>--with-local-prefix</samp> <strong>must not</strong> 453 1.1.1.14 mrg contain any of the system’s standard header files. If it did contain 454 1.1 mrg them, certain programs would be miscompiled (including GNU Emacs, on 455 1.1 mrg certain targets), because this would override and nullify the header 456 1.1.1.14 mrg file corrections made by the <code>fixincludes</code> script. 457 1.1.1.14 mrg </p> 458 1.1.1.14 mrg <p>Indications are that people who use this option use it based on mistaken 459 1.1 mrg ideas of what it is for. People use it as if it specified where to 460 1.1 mrg install part of GCC. Perhaps they make this assumption because 461 1.1 mrg installing GCC creates the directory. 462 1.1.1.14 mrg </p> 463 1.1.1.14 mrg </dd> 464 1.1.1.20 mrg <dt><span><code>--with-gcc-major-version-only</code></span></dt> 465 1.1.1.14 mrg <dd><p>Specifies that GCC should use only the major number rather than 466 1.1.1.10 mrg <var>major</var>.<var>minor</var>.<var>patchlevel</var> in filesystem paths. 467 1.1.1.14 mrg </p> 468 1.1.1.14 mrg </dd> 469 1.1.1.20 mrg <dt><span><code>--with-native-system-header-dir=<var>dirname</var></code></span></dt> 470 1.1.1.14 mrg <dd><p>Specifies that <var>dirname</var> is the directory that contains native system 471 1.1.1.14 mrg header files, rather than <samp>/usr/include</samp>. This option is most useful 472 1.1.1.3 skrll if you are creating a compiler that should be isolated from the system 473 1.1.1.3 skrll as much as possible. It is most commonly used with the 474 1.1.1.14 mrg <samp>--with-sysroot</samp> option and will cause GCC to search 475 1.1.1.3 skrll <var>dirname</var> inside the system root specified by that option. 476 1.1.1.14 mrg </p> 477 1.1.1.14 mrg </dd> 478 1.1.1.20 mrg <dt><span><code>--enable-shared[=<var>package</var>[,…]]</code></span></dt> 479 1.1.1.14 mrg <dd><p>Build shared versions of libraries, if shared libraries are supported on 480 1.1 mrg the target platform. Unlike GCC 2.95.x and earlier, shared libraries 481 1.1 mrg are enabled by default on all platforms that support shared libraries. 482 1.1.1.14 mrg </p> 483 1.1.1.14 mrg <p>If a list of packages is given as an argument, build shared libraries 484 1.1 mrg only for the listed packages. For other packages, only static libraries 485 1.1 mrg will be built. Package names currently recognized in the GCC tree are 486 1.1.1.14 mrg ‘<samp>libgcc</samp>’ (also known as ‘<samp>gcc</samp>’), ‘<samp>libstdc++</samp>’ (not 487 1.1.1.14 mrg ‘<samp>libstdc++-v3</samp>’), ‘<samp>libffi</samp>’, ‘<samp>zlib</samp>’, ‘<samp>boehm-gc</samp>’, 488 1.1.1.15 mrg ‘<samp>ada</samp>’, ‘<samp>libada</samp>’, ‘<samp>libgo</samp>’, ‘<samp>libobjc</samp>’, and ‘<samp>libphobos</samp>’. 489 1.1.1.14 mrg Note ‘<samp>libiberty</samp>’ does not support shared libraries at all. 490 1.1.1.14 mrg </p> 491 1.1.1.14 mrg <p>Use <samp>--disable-shared</samp> to build only static libraries. Note that 492 1.1.1.14 mrg <samp>--disable-shared</samp> does not accept a list of package names as 493 1.1.1.14 mrg argument, only <samp>--enable-shared</samp> does. 494 1.1.1.14 mrg </p> 495 1.1.1.14 mrg <p>Contrast with <samp>--enable-host-shared</samp>, which affects <em>host</em> 496 1.1.1.6 mrg code. 497 1.1.1.14 mrg </p> 498 1.1.1.14 mrg </dd> 499 1.1.1.20 mrg <dt><span><code>--enable-host-shared</code></span></dt> 500 1.1.1.14 mrg <dd><p>Specify that the <em>host</em> code should be built into position-independent 501 1.1.1.6 mrg machine code (with -fPIC), allowing it to be used within shared libraries, 502 1.1.1.6 mrg but yielding a slightly slower compiler. 503 1.1.1.14 mrg </p> 504 1.1.1.14 mrg <p>This option is required when building the libgccjit.so library. 505 1.1.1.14 mrg </p> 506 1.1.1.14 mrg <p>Contrast with <samp>--enable-shared</samp>, which affects <em>target</em> 507 1.1.1.6 mrg libraries. 508 1.1.1.14 mrg </p> 509 1.1.1.14 mrg </dd> 510 1.1.1.20 mrg <dt><span><code><span id="with-gnu-as"></span>--with-gnu-as</code></span></dt> 511 1.1.1.14 mrg <dd><p>Specify that the compiler should assume that the 512 1.1 mrg assembler it finds is the GNU assembler. However, this does not modify 513 1.1 mrg the rules to find an assembler and will result in confusion if the 514 1.1 mrg assembler found is not actually the GNU assembler. (Confusion may also 515 1.1 mrg result if the compiler finds the GNU assembler but has not been 516 1.1.1.14 mrg configured with <samp>--with-gnu-as</samp>.) If you have more than one 517 1.1 mrg assembler installed on your system, you may want to use this option in 518 1.1.1.14 mrg connection with <samp>--with-as=<var>pathname</var></samp> or 519 1.1.1.14 mrg <samp>--with-build-time-tools=<var>pathname</var></samp>. 520 1.1.1.14 mrg </p> 521 1.1.1.14 mrg <p>The following systems are the only ones where it makes a difference 522 1.1 mrg whether you use the GNU assembler. On any other system, 523 1.1.1.14 mrg <samp>--with-gnu-as</samp> has no effect. 524 1.1.1.14 mrg </p> 525 1.1.1.14 mrg <ul> 526 1.1.1.14 mrg <li> ‘<samp>hppa1.0-<var>any</var>-<var>any</var></samp>’ 527 1.1.1.14 mrg </li><li> ‘<samp>hppa1.1-<var>any</var>-<var>any</var></samp>’ 528 1.1.1.14 mrg </li><li> ‘<samp>sparc-sun-solaris2.<var>any</var></samp>’ 529 1.1.1.14 mrg </li><li> ‘<samp>sparc64-<var>any</var>-solaris2.<var>any</var></samp>’ 530 1.1.1.14 mrg </li></ul> 531 1.1.1.14 mrg 532 1.1.1.14 mrg </dd> 533 1.1.1.20 mrg <dt><span><code><span id="with-as"></span>--with-as=<var>pathname</var></code></span></dt> 534 1.1.1.14 mrg <dd><p>Specify that the compiler should use the assembler pointed to by 535 1.1 mrg <var>pathname</var>, rather than the one found by the standard rules to find 536 1.1 mrg an assembler, which are: 537 1.1.1.14 mrg </p><ul> 538 1.1.1.14 mrg <li> Unless GCC is being built with a cross compiler, check the 539 1.1.1.14 mrg <samp><var>libexec</var>/gcc/<var>target</var>/<var>version</var></samp> directory. 540 1.1.1.14 mrg <var>libexec</var> defaults to <samp><var>exec-prefix</var>/libexec</samp>; 541 1.1 mrg <var>exec-prefix</var> defaults to <var>prefix</var>, which 542 1.1.1.14 mrg defaults to <samp>/usr/local</samp> unless overridden by the 543 1.1.1.14 mrg <samp>--prefix=<var>pathname</var></samp> switch described above. <var>target</var> 544 1.1.1.14 mrg is the target system triple, such as ‘<samp>sparc-sun-solaris2.7</samp>’, and 545 1.1 mrg <var>version</var> denotes the GCC version, such as 3.0. 546 1.1 mrg 547 1.1.1.14 mrg </li><li> If the target system is the same that you are building on, check 548 1.1.1.14 mrg operating system specific directories (e.g. <samp>/usr/ccs/bin</samp> on 549 1.1.1.16 mrg Solaris 2). 550 1.1 mrg 551 1.1.1.14 mrg </li><li> Check in the <code>PATH</code> for a tool whose name is prefixed by the 552 1.1 mrg target system triple. 553 1.1 mrg 554 1.1.1.14 mrg </li><li> Check in the <code>PATH</code> for a tool whose name is not prefixed by the 555 1.1 mrg target system triple, if the host and target system triple are 556 1.1 mrg the same (in other words, we use a host tool if it can be used for 557 1.1.1.14 mrg the target as well). 558 1.1.1.14 mrg </li></ul> 559 1.1 mrg 560 1.1.1.14 mrg <p>You may want to use <samp>--with-as</samp> if no assembler 561 1.1 mrg is installed in the directories listed above, or if you have multiple 562 1.1 mrg assemblers installed and want to choose one that is not found by the 563 1.1 mrg above rules. 564 1.1.1.14 mrg </p> 565 1.1.1.14 mrg </dd> 566 1.1.1.20 mrg <dt><span><code><span id="with-gnu-ld"></span>--with-gnu-ld</code></span></dt> 567 1.1.1.14 mrg <dd><p>Same as <a href="#with-gnu-as"><samp>--with-gnu-as</samp></a> 568 1.1 mrg but for the linker. 569 1.1.1.14 mrg </p> 570 1.1.1.14 mrg </dd> 571 1.1.1.20 mrg <dt><span><code>--with-ld=<var>pathname</var></code></span></dt> 572 1.1.1.14 mrg <dd><p>Same as <a href="#with-as"><samp>--with-as</samp></a> 573 1.1 mrg but for the linker. 574 1.1.1.14 mrg </p> 575 1.1.1.14 mrg </dd> 576 1.1.1.20 mrg <dt><span><code>--with-dsymutil=<var>pathname</var></code></span></dt> 577 1.1.1.17 mrg <dd><p>Same as <a href="#with-as"><samp>--with-as</samp></a> 578 1.1.1.17 mrg but for the debug linker (only used on Darwin platforms so far). 579 1.1.1.17 mrg </p> 580 1.1.1.17 mrg </dd> 581 1.1.1.20 mrg <dt><span><code>--with-tls=<var>dialect</var></code></span></dt> 582 1.1.1.14 mrg <dd><p>Specify the default TLS dialect, for systems were there is a choice. 583 1.1.1.3 skrll For ARM targets, possible values for <var>dialect</var> are <code>gnu</code> or 584 1.1.1.3 skrll <code>gnu2</code>, which select between the original GNU dialect and the GNU TLS 585 1.1.1.3 skrll descriptor-based dialect. 586 1.1.1.14 mrg </p> 587 1.1.1.14 mrg </dd> 588 1.1.1.20 mrg <dt><span><code>--enable-multiarch</code></span></dt> 589 1.1.1.14 mrg <dd><p>Specify whether to enable or disable multiarch support. The default is 590 1.1.1.3 skrll to check for glibc start files in a multiarch location, and enable it 591 1.1.1.3 skrll if the files are found. The auto detection is enabled for native builds, 592 1.1.1.14 mrg and for cross builds configured with <samp>--with-sysroot</samp>, and without 593 1.1.1.14 mrg <samp>--with-native-system-header-dir</samp>. 594 1.1.1.3 skrll More documentation about multiarch can be found at 595 1.1.1.8 mrg <a href="https://wiki.debian.org/Multiarch">https://wiki.debian.org/Multiarch</a>. 596 1.1.1.14 mrg </p> 597 1.1.1.14 mrg </dd> 598 1.1.1.20 mrg <dt><span><code>--enable-sjlj-exceptions</code></span></dt> 599 1.1.1.14 mrg <dd><p>Force use of the <code>setjmp</code>/<code>longjmp</code>-based scheme for exceptions. 600 1.1.1.14 mrg ‘<samp>configure</samp>’ ordinarily picks the correct value based on the platform. 601 1.1.1.7 mrg Only use this option if you are sure you need a different setting. 602 1.1.1.14 mrg </p> 603 1.1.1.14 mrg </dd> 604 1.1.1.20 mrg <dt><span><code>--enable-vtable-verify</code></span></dt> 605 1.1.1.14 mrg <dd><p>Specify whether to enable or disable the vtable verification feature. 606 1.1.1.6 mrg Enabling this feature causes libstdc++ to be built with its virtual calls 607 1.1.1.6 mrg in verifiable mode. This means that, when linked with libvtv, every 608 1.1.1.6 mrg virtual call in libstdc++ will verify the vtable pointer through which the 609 1.1.1.6 mrg call will be made before actually making the call. If not linked with libvtv, 610 1.1.1.14 mrg the verifier will call stub functions (in libstdc++ itself) and do nothing. 611 1.1.1.6 mrg If vtable verification is disabled, then libstdc++ is not built with its 612 1.1.1.6 mrg virtual calls in verifiable mode at all. However the libvtv library will 613 1.1.1.14 mrg still be built (see <samp>--disable-libvtv</samp> to turn off building libvtv). 614 1.1.1.14 mrg <samp>--disable-vtable-verify</samp> is the default. 615 1.1.1.14 mrg </p> 616 1.1.1.14 mrg </dd> 617 1.1.1.20 mrg <dt><span><code>--disable-gcov</code></span></dt> 618 1.1.1.15 mrg <dd><p>Specify that the run-time library used for coverage analysis 619 1.1.1.15 mrg and associated host tools should not be built. 620 1.1.1.15 mrg </p> 621 1.1.1.15 mrg </dd> 622 1.1.1.20 mrg <dt><span><code>--disable-multilib</code></span></dt> 623 1.1.1.14 mrg <dd><p>Specify that multiple target 624 1.1 mrg libraries to support different target variants, calling 625 1.1 mrg conventions, etc. should not be built. The default is to build a 626 1.1 mrg predefined set of them. 627 1.1.1.14 mrg </p> 628 1.1.1.14 mrg <p>Some targets provide finer-grained control over which multilibs are built 629 1.1.1.14 mrg (e.g., <samp>--disable-softfloat</samp>): 630 1.1.1.14 mrg </p><dl compact="compact"> 631 1.1.1.20 mrg <dt><span><code>arm-*-*</code></span></dt> 632 1.1.1.14 mrg <dd><p>fpu, 26bit, underscore, interwork, biendian, nofmult. 633 1.1.1.14 mrg </p> 634 1.1.1.14 mrg </dd> 635 1.1.1.20 mrg <dt><span><code>m68*-*-*</code></span></dt> 636 1.1.1.14 mrg <dd><p>softfloat, m68881, m68000, m68020. 637 1.1.1.14 mrg </p> 638 1.1.1.14 mrg </dd> 639 1.1.1.20 mrg <dt><span><code>mips*-*-*</code></span></dt> 640 1.1.1.14 mrg <dd><p>single-float, biendian, softfloat. 641 1.1.1.14 mrg </p> 642 1.1.1.14 mrg </dd> 643 1.1.1.20 mrg <dt><span><code>msp430-*-*</code></span></dt> 644 1.1.1.16 mrg <dd><p>no-exceptions 645 1.1.1.16 mrg </p> 646 1.1.1.16 mrg </dd> 647 1.1.1.20 mrg <dt><span><code>powerpc*-*-*, rs6000*-*-*</code></span></dt> 648 1.1.1.14 mrg <dd><p>aix64, pthread, softfloat, powercpu, powerpccpu, powerpcos, biendian, 649 1.1 mrg sysv, aix. 650 1.1.1.14 mrg </p> 651 1.1.1.14 mrg </dd> 652 1.1.1.14 mrg </dl> 653 1.1 mrg 654 1.1.1.14 mrg </dd> 655 1.1.1.20 mrg <dt><span><code>--with-multilib-list=<var>list</var></code></span></dt> 656 1.1.1.20 mrg <dt><span><code>--without-multilib-list</code></span></dt> 657 1.1.1.14 mrg <dd><p>Specify what multilibs to build. <var>list</var> is a comma separated list of 658 1.1.1.10 mrg values, possibly consisting of a single value. Currently only implemented 659 1.1.1.19 mrg for aarch64*-*-*, arm*-*-*, loongarch64-*-*, riscv*-*-*, sh*-*-* and 660 1.1.1.19 mrg x86-64-*-linux*. The accepted values and meaning for each target is given 661 1.1.1.19 mrg below. 662 1.1.1.14 mrg </p> 663 1.1.1.14 mrg <dl compact="compact"> 664 1.1.1.20 mrg <dt><span><code>aarch64*-*-*</code></span></dt> 665 1.1.1.14 mrg <dd><p><var>list</var> is a comma separated list of <code>ilp32</code>, and <code>lp64</code> 666 1.1.1.14 mrg to enable ILP32 and LP64 run-time libraries, respectively. If 667 1.1.1.14 mrg <var>list</var> is empty, then there will be no multilibs and only the 668 1.1.1.14 mrg default run-time library will be built. If <var>list</var> is 669 1.1.1.14 mrg <code>default</code> or –with-multilib-list= is not specified, then the 670 1.1.1.14 mrg default set of libraries is selected based on the value of 671 1.1.1.14 mrg <samp>--target</samp>. 672 1.1.1.14 mrg </p> 673 1.1.1.14 mrg </dd> 674 1.1.1.20 mrg <dt><span><code>arm*-*-*</code></span></dt> 675 1.1.1.15 mrg <dd><p><var>list</var> is a comma separated list of <code>aprofile</code> and 676 1.1.1.15 mrg <code>rmprofile</code> to build multilibs for A or R and M architecture 677 1.1.1.15 mrg profiles respectively. Note that, due to some limitation of the current 678 1.1.1.15 mrg multilib framework, using the combined <code>aprofile,rmprofile</code> 679 1.1.1.15 mrg multilibs selects in some cases a less optimal multilib than when using 680 1.1.1.15 mrg the multilib profile for the architecture targetted. The special value 681 1.1.1.15 mrg <code>default</code> is also accepted and is equivalent to omitting the 682 1.1.1.15 mrg option, i.e., only the default run-time library will be enabled. 683 1.1.1.15 mrg </p> 684 1.1.1.15 mrg <p><var>list</var> may instead contain <code>@name</code>, to use the multilib 685 1.1.1.15 mrg configuration Makefile fragment <samp>name</samp> in <samp>gcc/config/arm</samp> in 686 1.1.1.15 mrg the source tree (it is part of the corresponding sources, after all). 687 1.1.1.15 mrg It is recommended, but not required, that files used for this purpose to 688 1.1.1.15 mrg be named starting with <samp>t-ml-</samp>, to make their intended purpose 689 1.1.1.15 mrg self-evident, in line with GCC conventions. Such files enable custom, 690 1.1.1.15 mrg user-chosen multilib lists to be configured. Whether multiple such 691 1.1.1.15 mrg files can be used together depends on the contents of the supplied 692 1.1.1.15 mrg files. See <samp>gcc/config/arm/t-multilib</samp> and its supplementary 693 1.1.1.15 mrg <samp>gcc/config/arm/t-*profile</samp> files for an example of what such 694 1.1.1.15 mrg Makefile fragments might look like for this version of GCC. The macros 695 1.1.1.15 mrg expected to be defined in these fragments are not stable across GCC 696 1.1.1.15 mrg releases, so make sure they define the <code>MULTILIB</code>-related macros 697 1.1.1.15 mrg expected by the version of GCC you are building. 698 1.1.1.15 mrg See “Target Makefile Fragments” in the internals manual. 699 1.1.1.14 mrg </p> 700 1.1.1.14 mrg <p>The table below gives the combination of ISAs, architectures, FPUs and 701 1.1.1.15 mrg floating-point ABIs for which multilibs are built for each predefined 702 1.1.1.15 mrg profile. The union of these options is considered when specifying both 703 1.1.1.15 mrg <code>aprofile</code> and <code>rmprofile</code>. 704 1.1.1.14 mrg </p> 705 1.1.1.14 mrg <table> 706 1.1.1.14 mrg <tr><td width="15%">Option</td><td width="28%">aprofile</td><td width="30%">rmprofile</td></tr> 707 1.1.1.14 mrg <tr><td width="15%">ISAs</td><td width="28%"><code>-marm</code> and <code>-mthumb</code></td><td width="30%"><code>-mthumb</code></td></tr> 708 1.1.1.14 mrg <tr><td width="15%">Architectures<br><br><br><br><br><br></td><td width="28%">default architecture<br> 709 1.1.1.10 mrg <code>-march=armv7-a</code><br> 710 1.1.1.10 mrg <code>-march=armv7ve</code><br> 711 1.1.1.14 mrg <code>-march=armv8-a</code><br><br><br></td><td width="30%">default architecture<br> 712 1.1.1.10 mrg <code>-march=armv6s-m</code><br> 713 1.1.1.10 mrg <code>-march=armv7-m</code><br> 714 1.1.1.10 mrg <code>-march=armv7e-m</code><br> 715 1.1.1.10 mrg <code>-march=armv8-m.base</code><br> 716 1.1.1.10 mrg <code>-march=armv8-m.main</code><br> 717 1.1.1.14 mrg <code>-march=armv7</code></td></tr> 718 1.1.1.14 mrg <tr><td width="15%">FPUs<br><br><br><br><br></td><td width="28%">none<br> 719 1.1.1.10 mrg <code>-mfpu=vfpv3-d16</code><br> 720 1.1.1.10 mrg <code>-mfpu=neon</code><br> 721 1.1.1.10 mrg <code>-mfpu=vfpv4-d16</code><br> 722 1.1.1.10 mrg <code>-mfpu=neon-vfpv4</code><br> 723 1.1.1.14 mrg <code>-mfpu=neon-fp-armv8</code></td><td width="30%">none<br> 724 1.1.1.10 mrg <code>-mfpu=vfpv3-d16</code><br> 725 1.1.1.10 mrg <code>-mfpu=fpv4-sp-d16</code><br> 726 1.1.1.10 mrg <code>-mfpu=fpv5-sp-d16</code><br> 727 1.1.1.14 mrg <code>-mfpu=fpv5-d16</code><br></td></tr> 728 1.1.1.14 mrg <tr><td width="15%">floating-point ABIs<br><br></td><td width="28%"><code>-mfloat-abi=soft</code><br> 729 1.1.1.10 mrg <code>-mfloat-abi=softfp</code><br> 730 1.1.1.14 mrg <code>-mfloat-abi=hard</code></td><td width="30%"><code>-mfloat-abi=soft</code><br> 731 1.1.1.10 mrg <code>-mfloat-abi=softfp</code><br> 732 1.1.1.14 mrg <code>-mfloat-abi=hard</code></td></tr> 733 1.1.1.14 mrg </table> 734 1.1.1.10 mrg 735 1.1.1.14 mrg </dd> 736 1.1.1.20 mrg <dt><span><code>loongarch*-*-*</code></span></dt> 737 1.1.1.19 mrg <dd><p><var>list</var> is a comma-separated list of the following ABI identifiers: 738 1.1.1.19 mrg <code>lp64d[/base]</code> <code>lp64f[/base]</code> <code>lp64d[/base]</code>, where the 739 1.1.1.19 mrg <code>/base</code> suffix may be omitted, to enable their respective run-time 740 1.1.1.19 mrg libraries. If <var>list</var> is empty or <code>default</code>, 741 1.1.1.19 mrg or if <samp>--with-multilib-list</samp> is not specified, then the default ABI 742 1.1.1.19 mrg as specified by <samp>--with-abi</samp> or implied by <samp>--target</samp> is selected. 743 1.1.1.19 mrg </p> 744 1.1.1.19 mrg </dd> 745 1.1.1.20 mrg <dt><span><code>riscv*-*-*</code></span></dt> 746 1.1.1.15 mrg <dd><p><var>list</var> is a single ABI name. The target architecture must be either 747 1.1.1.15 mrg <code>rv32gc</code> or <code>rv64gc</code>. This will build a single multilib for the 748 1.1.1.15 mrg specified architecture and ABI pair. If <code>--with-multilib-list</code> is not 749 1.1.1.15 mrg given, then a default set of multilibs is selected based on the value of 750 1.1.1.15 mrg <samp>--target</samp>. This is usually a large set of multilibs. 751 1.1.1.15 mrg </p> 752 1.1.1.15 mrg </dd> 753 1.1.1.20 mrg <dt><span><code>sh*-*-*</code></span></dt> 754 1.1.1.14 mrg <dd><p><var>list</var> is a comma separated list of CPU names. These must be of the 755 1.1 mrg form <code>sh*</code> or <code>m*</code> (in which case they match the compiler option 756 1.1 mrg for that processor). The list should not contain any endian options - 757 1.1.1.14 mrg these are handled by <samp>--with-endian</samp>. 758 1.1.1.14 mrg </p> 759 1.1.1.14 mrg <p>If <var>list</var> is empty, then there will be no multilibs for extra 760 1.1 mrg processors. The multilib for the secondary endian remains enabled. 761 1.1.1.14 mrg </p> 762 1.1.1.14 mrg <p>As a special case, if an entry in the list starts with a <code>!</code> 763 1.1.1.14 mrg (exclamation point), then it is added to the list of excluded multilibs. 764 1.1.1.14 mrg Entries of this sort should be compatible with ‘<samp>MULTILIB_EXCLUDES</samp>’ 765 1.1 mrg (once the leading <code>!</code> has been stripped). 766 1.1.1.14 mrg </p> 767 1.1.1.14 mrg <p>If <samp>--with-multilib-list</samp> is not given, then a default set of 768 1.1.1.14 mrg multilibs is selected based on the value of <samp>--target</samp>. This is 769 1.1 mrg usually the complete set of libraries, but some targets imply a more 770 1.1 mrg specialized subset. 771 1.1.1.14 mrg </p> 772 1.1.1.14 mrg <p>Example 1: to configure a compiler for SH4A only, but supporting both 773 1.1.1.13 mrg endians, with little endian being the default: 774 1.1.1.20 mrg </p><div class="example"> 775 1.1.1.20 mrg <pre class="example">--with-cpu=sh4a --with-endian=little,big --with-multilib-list= 776 1.1.1.14 mrg </pre></div> 777 1.1.1.14 mrg 778 1.1.1.14 mrg <p>Example 2: to configure a compiler for both SH4A and SH4AL-DSP, but with 779 1.1 mrg only little endian SH4AL: 780 1.1.1.20 mrg </p><div class="example"> 781 1.1.1.20 mrg <pre class="example">--with-cpu=sh4a --with-endian=little,big \ 782 1.1.1.14 mrg --with-multilib-list=sh4al,!mb/m4al 783 1.1.1.14 mrg </pre></div> 784 1.1.1.14 mrg 785 1.1.1.14 mrg </dd> 786 1.1.1.20 mrg <dt><span><code>x86-64-*-linux*</code></span></dt> 787 1.1.1.14 mrg <dd><p><var>list</var> is a comma separated list of <code>m32</code>, <code>m64</code> and 788 1.1.1.3 skrll <code>mx32</code> to enable 32-bit, 64-bit and x32 run-time libraries, 789 1.1.1.3 skrll respectively. If <var>list</var> is empty, then there will be no multilibs 790 1.1.1.3 skrll and only the default run-time library will be enabled. 791 1.1.1.14 mrg </p> 792 1.1.1.14 mrg <p>If <samp>--with-multilib-list</samp> is not given, then only 32-bit and 793 1.1.1.14 mrg 64-bit run-time libraries will be enabled. 794 1.1.1.14 mrg </p></dd> 795 1.1.1.3 skrll </dl> 796 1.1.1.3 skrll 797 1.1.1.14 mrg </dd> 798 1.1.1.20 mrg <dt><span><code>--with-multilib-generator=<var>config</var></code></span></dt> 799 1.1.1.19 mrg <dd><p>Specify what multilibs to build. <var>config</var> is a semicolon separated list of 800 1.1.1.19 mrg values, possibly consisting of a single value. Currently only implemented 801 1.1.1.19 mrg for riscv*-*-elf*. The accepted values and meanings are given below. 802 1.1.1.19 mrg </p> 803 1.1.1.19 mrg 804 1.1.1.19 mrg <p>Every config is constructed with four components: architecture string, ABI, 805 1.1.1.19 mrg reuse rule with architecture string and reuse rule with sub-extension. 806 1.1.1.19 mrg </p> 807 1.1.1.19 mrg <p>Example 1: Add multi-lib suppport for rv32i with ilp32. 808 1.1.1.20 mrg </p><div class="example"> 809 1.1.1.20 mrg <pre class="example">rv32i-ilp32-- 810 1.1.1.19 mrg </pre></div> 811 1.1.1.19 mrg 812 1.1.1.19 mrg <p>Example 2: Add multi-lib suppport for rv32i with ilp32 and rv32imafd with ilp32. 813 1.1.1.20 mrg </p><div class="example"> 814 1.1.1.20 mrg <pre class="example">rv32i-ilp32--;rv32imafd-ilp32-- 815 1.1.1.19 mrg </pre></div> 816 1.1.1.19 mrg 817 1.1.1.19 mrg <p>Example 3: Add multi-lib suppport for rv32i with ilp32; rv32im with ilp32 and 818 1.1.1.19 mrg rv32ic with ilp32 will reuse this multi-lib set. 819 1.1.1.20 mrg </p><div class="example"> 820 1.1.1.20 mrg <pre class="example">rv32i-ilp32-rv32im-c 821 1.1.1.19 mrg </pre></div> 822 1.1.1.19 mrg 823 1.1.1.19 mrg <p>Example 4: Add multi-lib suppport for rv64ima with lp64; rv64imaf with lp64, 824 1.1.1.19 mrg rv64imac with lp64 and rv64imafc with lp64 will reuse this multi-lib set. 825 1.1.1.20 mrg </p><div class="example"> 826 1.1.1.20 mrg <pre class="example">rv64ima-lp64--f,c,fc 827 1.1.1.19 mrg </pre></div> 828 1.1.1.19 mrg 829 1.1.1.19 mrg <p><samp>--with-multilib-generator</samp> have an optional configuration argument 830 1.1.1.19 mrg <samp>--cmodel=val</samp> for code model, this option will expand with other 831 1.1.1.19 mrg config options, <var>val</var> is a comma separated list of possible code model, 832 1.1.1.19 mrg currently we support medlow and medany. 833 1.1.1.19 mrg </p> 834 1.1.1.19 mrg <p>Example 5: Add multi-lib suppport for rv64ima with lp64; rv64ima with lp64 and 835 1.1.1.19 mrg medlow code model 836 1.1.1.20 mrg </p><div class="example"> 837 1.1.1.20 mrg <pre class="example">rv64ima-lp64--;--cmodel=medlow 838 1.1.1.19 mrg </pre></div> 839 1.1.1.19 mrg 840 1.1.1.19 mrg <p>Example 6: Add multi-lib suppport for rv64ima with lp64; rv64ima with lp64 and 841 1.1.1.19 mrg medlow code model; rv64ima with lp64 and medany code model 842 1.1.1.20 mrg </p><div class="example"> 843 1.1.1.20 mrg <pre class="example">rv64ima-lp64--;--cmodel=medlow,medany 844 1.1.1.19 mrg </pre></div> 845 1.1.1.19 mrg 846 1.1.1.19 mrg </dd> 847 1.1.1.20 mrg <dt><span><code>--with-endian=<var>endians</var></code></span></dt> 848 1.1.1.14 mrg <dd><p>Specify what endians to use. 849 1.1 mrg Currently only implemented for sh*-*-*. 850 1.1.1.14 mrg </p> 851 1.1.1.14 mrg <p><var>endians</var> may be one of the following: 852 1.1.1.14 mrg </p><dl compact="compact"> 853 1.1.1.20 mrg <dt><span><code>big</code></span></dt> 854 1.1.1.14 mrg <dd><p>Use big endian exclusively. 855 1.1.1.14 mrg </p></dd> 856 1.1.1.20 mrg <dt><span><code>little</code></span></dt> 857 1.1.1.14 mrg <dd><p>Use little endian exclusively. 858 1.1.1.14 mrg </p></dd> 859 1.1.1.20 mrg <dt><span><code>big,little</code></span></dt> 860 1.1.1.14 mrg <dd><p>Use big endian by default. Provide a multilib for little endian. 861 1.1.1.14 mrg </p></dd> 862 1.1.1.20 mrg <dt><span><code>little,big</code></span></dt> 863 1.1.1.14 mrg <dd><p>Use little endian by default. Provide a multilib for big endian. 864 1.1.1.14 mrg </p></dd> 865 1.1 mrg </dl> 866 1.1 mrg 867 1.1.1.14 mrg </dd> 868 1.1.1.20 mrg <dt><span><code>--enable-threads</code></span></dt> 869 1.1.1.14 mrg <dd><p>Specify that the target 870 1.1 mrg supports threads. This affects the Objective-C compiler and runtime 871 1.1.1.14 mrg library, and exception handling for other languages like C++. 872 1.1 mrg On some systems, this is the default. 873 1.1.1.14 mrg </p> 874 1.1.1.14 mrg <p>In general, the best (and, in many cases, the only known) threading 875 1.1 mrg model available will be configured for use. Beware that on some 876 1.1 mrg systems, GCC has not been taught what threading models are generally 877 1.1.1.14 mrg available for the system. In this case, <samp>--enable-threads</samp> is an 878 1.1.1.14 mrg alias for <samp>--enable-threads=single</samp>. 879 1.1.1.14 mrg </p> 880 1.1.1.14 mrg </dd> 881 1.1.1.20 mrg <dt><span><code>--disable-threads</code></span></dt> 882 1.1.1.14 mrg <dd><p>Specify that threading support should be disabled for the system. 883 1.1.1.14 mrg This is an alias for <samp>--enable-threads=single</samp>. 884 1.1.1.14 mrg </p> 885 1.1.1.14 mrg </dd> 886 1.1.1.20 mrg <dt><span><code>--enable-threads=<var>lib</var></code></span></dt> 887 1.1.1.14 mrg <dd><p>Specify that 888 1.1 mrg <var>lib</var> is the thread support library. This affects the Objective-C 889 1.1 mrg compiler and runtime library, and exception handling for other languages 890 1.1.1.10 mrg like C++. The possibilities for <var>lib</var> are: 891 1.1.1.14 mrg </p> 892 1.1.1.14 mrg <dl compact="compact"> 893 1.1.1.20 mrg <dt><span><code>aix</code></span></dt> 894 1.1.1.14 mrg <dd><p>AIX thread support. 895 1.1.1.14 mrg </p></dd> 896 1.1.1.20 mrg <dt><span><code>dce</code></span></dt> 897 1.1.1.14 mrg <dd><p>DCE thread support. 898 1.1.1.14 mrg </p></dd> 899 1.1.1.20 mrg <dt><span><code>lynx</code></span></dt> 900 1.1.1.14 mrg <dd><p>LynxOS thread support. 901 1.1.1.14 mrg </p></dd> 902 1.1.1.20 mrg <dt><span><code>mipssde</code></span></dt> 903 1.1.1.14 mrg <dd><p>MIPS SDE thread support. 904 1.1.1.14 mrg </p></dd> 905 1.1.1.20 mrg <dt><span><code>no</code></span></dt> 906 1.1.1.14 mrg <dd><p>This is an alias for ‘<samp>single</samp>’. 907 1.1.1.14 mrg </p></dd> 908 1.1.1.20 mrg <dt><span><code>posix</code></span></dt> 909 1.1.1.14 mrg <dd><p>Generic POSIX/Unix98 thread support. 910 1.1.1.14 mrg </p></dd> 911 1.1.1.20 mrg <dt><span><code>rtems</code></span></dt> 912 1.1.1.14 mrg <dd><p>RTEMS thread support. 913 1.1.1.14 mrg </p></dd> 914 1.1.1.20 mrg <dt><span><code>single</code></span></dt> 915 1.1.1.14 mrg <dd><p>Disable thread support, should work for all platforms. 916 1.1.1.14 mrg </p></dd> 917 1.1.1.20 mrg <dt><span><code>tpf</code></span></dt> 918 1.1.1.14 mrg <dd><p>TPF thread support. 919 1.1.1.14 mrg </p></dd> 920 1.1.1.20 mrg <dt><span><code>vxworks</code></span></dt> 921 1.1.1.14 mrg <dd><p>VxWorks thread support. 922 1.1.1.14 mrg </p></dd> 923 1.1.1.20 mrg <dt><span><code>win32</code></span></dt> 924 1.1.1.14 mrg <dd><p>Microsoft Win32 API thread support. 925 1.1.1.14 mrg </p></dd> 926 1.1 mrg </dl> 927 1.1 mrg 928 1.1.1.14 mrg </dd> 929 1.1.1.20 mrg <dt><span><code>--enable-tls</code></span></dt> 930 1.1.1.14 mrg <dd><p>Specify that the target supports TLS (Thread Local Storage). Usually 931 1.1 mrg configure can correctly determine if TLS is supported. In cases where 932 1.1 mrg it guesses incorrectly, TLS can be explicitly enabled or disabled with 933 1.1.1.14 mrg <samp>--enable-tls</samp> or <samp>--disable-tls</samp>. This can happen if 934 1.1 mrg the assembler supports TLS but the C library does not, or if the 935 1.1 mrg assumptions made by the configure test are incorrect. 936 1.1.1.14 mrg </p> 937 1.1.1.14 mrg </dd> 938 1.1.1.20 mrg <dt><span><code>--disable-tls</code></span></dt> 939 1.1.1.14 mrg <dd><p>Specify that the target does not support TLS. 940 1.1.1.14 mrg This is an alias for <samp>--enable-tls=no</samp>. 941 1.1.1.14 mrg </p> 942 1.1.1.14 mrg </dd> 943 1.1.1.20 mrg <dt><span><code>--disable-tm-clone-registry</code></span></dt> 944 1.1.1.16 mrg <dd><p>Disable TM clone registry in libgcc. It is enabled in libgcc by default. 945 1.1.1.16 mrg This option helps to reduce code size for embedded targets which do 946 1.1.1.16 mrg not use transactional memory. 947 1.1.1.16 mrg </p> 948 1.1.1.16 mrg </dd> 949 1.1.1.20 mrg <dt><span><code>--with-cpu=<var>cpu</var></code></span></dt> 950 1.1.1.20 mrg <dt><span><code>--with-cpu-32=<var>cpu</var></code></span></dt> 951 1.1.1.20 mrg <dt><span><code>--with-cpu-64=<var>cpu</var></code></span></dt> 952 1.1.1.14 mrg <dd><p>Specify which cpu variant the compiler should generate code for by default. 953 1.1.1.14 mrg <var>cpu</var> will be used as the default value of the <samp>-mcpu=</samp> switch. 954 1.1.1.6 mrg This option is only supported on some targets, including ARC, ARM, i386, M68k, 955 1.1.1.14 mrg PowerPC, and SPARC. It is mandatory for ARC. The <samp>--with-cpu-32</samp> and 956 1.1.1.14 mrg <samp>--with-cpu-64</samp> options specify separate default CPUs for 957 1.1.1.16 mrg 32-bit and 64-bit modes; these options are only supported for aarch64, i386, 958 1.1.1.8 mrg x86-64, PowerPC, and SPARC. 959 1.1.1.14 mrg </p> 960 1.1.1.14 mrg </dd> 961 1.1.1.20 mrg <dt><span><code>--with-schedule=<var>cpu</var></code></span></dt> 962 1.1.1.20 mrg <dt><span><code>--with-arch=<var>cpu</var></code></span></dt> 963 1.1.1.20 mrg <dt><span><code>--with-arch-32=<var>cpu</var></code></span></dt> 964 1.1.1.20 mrg <dt><span><code>--with-arch-64=<var>cpu</var></code></span></dt> 965 1.1.1.20 mrg <dt><span><code>--with-tune=<var>cpu</var></code></span></dt> 966 1.1.1.20 mrg <dt><span><code>--with-tune-32=<var>cpu</var></code></span></dt> 967 1.1.1.20 mrg <dt><span><code>--with-tune-64=<var>cpu</var></code></span></dt> 968 1.1.1.20 mrg <dt><span><code>--with-abi=<var>abi</var></code></span></dt> 969 1.1.1.20 mrg <dt><span><code>--with-fpu=<var>type</var></code></span></dt> 970 1.1.1.20 mrg <dt><span><code>--with-float=<var>type</var></code></span></dt> 971 1.1.1.14 mrg <dd><p>These configure options provide default values for the <samp>-mschedule=</samp>, 972 1.1.1.14 mrg <samp>-march=</samp>, <samp>-mtune=</samp>, <samp>-mabi=</samp>, and <samp>-mfpu=</samp> 973 1.1.1.14 mrg options and for <samp>-mhard-float</samp> or <samp>-msoft-float</samp>. As with 974 1.1.1.14 mrg <samp>--with-cpu</samp>, which switches will be accepted and acceptable values 975 1.1 mrg of the arguments depend on the target. 976 1.1.1.14 mrg </p> 977 1.1.1.14 mrg </dd> 978 1.1.1.20 mrg <dt><span><code>--with-mode=<var>mode</var></code></span></dt> 979 1.1.1.14 mrg <dd><p>Specify if the compiler should default to <samp>-marm</samp> or <samp>-mthumb</samp>. 980 1.1 mrg This option is only supported on ARM targets. 981 1.1.1.14 mrg </p> 982 1.1.1.14 mrg </dd> 983 1.1.1.20 mrg <dt><span><code>--with-stack-offset=<var>num</var></code></span></dt> 984 1.1.1.14 mrg <dd><p>This option sets the default for the -mstack-offset=<var>num</var> option, 985 1.1.1.3 skrll and will thus generally also control the setting of this option for 986 1.1.1.3 skrll libraries. This option is only supported on Epiphany targets. 987 1.1.1.14 mrg </p> 988 1.1.1.14 mrg </dd> 989 1.1.1.20 mrg <dt><span><code>--with-fpmath=<var>isa</var></code></span></dt> 990 1.1.1.14 mrg <dd><p>This options sets <samp>-mfpmath=sse</samp> by default and specifies the default 991 1.1.1.14 mrg ISA for floating-point arithmetics. You can select either ‘<samp>sse</samp>’ which 992 1.1.1.14 mrg enables <samp>-msse2</samp> or ‘<samp>avx</samp>’ which enables <samp>-mavx</samp> by default. 993 1.1.1.3 skrll This option is only supported on i386 and x86-64 targets. 994 1.1.1.14 mrg </p> 995 1.1.1.14 mrg </dd> 996 1.1.1.20 mrg <dt><span><code>--with-fp-32=<var>mode</var></code></span></dt> 997 1.1.1.14 mrg <dd><p>On MIPS targets, set the default value for the <samp>-mfp</samp> option when using 998 1.1.1.6 mrg the o32 ABI. The possibilities for <var>mode</var> are: 999 1.1.1.14 mrg </p><dl compact="compact"> 1000 1.1.1.20 mrg <dt><span><code>32</code></span></dt> 1001 1.1.1.14 mrg <dd><p>Use the o32 FP32 ABI extension, as with the <samp>-mfp32</samp> command-line 1002 1.1.1.14 mrg option. 1003 1.1.1.14 mrg </p></dd> 1004 1.1.1.20 mrg <dt><span><code>xx</code></span></dt> 1005 1.1.1.14 mrg <dd><p>Use the o32 FPXX ABI extension, as with the <samp>-mfpxx</samp> command-line 1006 1.1.1.14 mrg option. 1007 1.1.1.14 mrg </p></dd> 1008 1.1.1.20 mrg <dt><span><code>64</code></span></dt> 1009 1.1.1.14 mrg <dd><p>Use the o32 FP64 ABI extension, as with the <samp>-mfp64</samp> command-line 1010 1.1.1.14 mrg option. 1011 1.1.1.14 mrg </p></dd> 1012 1.1.1.6 mrg </dl> 1013 1.1.1.14 mrg <p>In the absence of this configuration option the default is to use the o32 1014 1.1.1.6 mrg FP32 ABI extension. 1015 1.1.1.14 mrg </p> 1016 1.1.1.14 mrg </dd> 1017 1.1.1.20 mrg <dt><span><code>--with-odd-spreg-32</code></span></dt> 1018 1.1.1.14 mrg <dd><p>On MIPS targets, set the <samp>-modd-spreg</samp> option by default when using 1019 1.1.1.6 mrg the o32 ABI. 1020 1.1.1.14 mrg </p> 1021 1.1.1.14 mrg </dd> 1022 1.1.1.20 mrg <dt><span><code>--without-odd-spreg-32</code></span></dt> 1023 1.1.1.14 mrg <dd><p>On MIPS targets, set the <samp>-mno-odd-spreg</samp> option by default when using 1024 1.1.1.6 mrg the o32 ABI. This is normally used in conjunction with 1025 1.1.1.14 mrg <samp>--with-fp-32=64</samp> in order to target the o32 FP64A ABI extension. 1026 1.1.1.14 mrg </p> 1027 1.1.1.14 mrg </dd> 1028 1.1.1.20 mrg <dt><span><code>--with-nan=<var>encoding</var></code></span></dt> 1029 1.1.1.14 mrg <dd><p>On MIPS targets, set the default encoding convention to use for the 1030 1.1.1.6 mrg special not-a-number (NaN) IEEE 754 floating-point data. The 1031 1.1.1.6 mrg possibilities for <var>encoding</var> are: 1032 1.1.1.14 mrg </p><dl compact="compact"> 1033 1.1.1.20 mrg <dt><span><code>legacy</code></span></dt> 1034 1.1.1.14 mrg <dd><p>Use the legacy encoding, as with the <samp>-mnan=legacy</samp> command-line 1035 1.1.1.14 mrg option. 1036 1.1.1.14 mrg </p></dd> 1037 1.1.1.20 mrg <dt><span><code>2008</code></span></dt> 1038 1.1.1.14 mrg <dd><p>Use the 754-2008 encoding, as with the <samp>-mnan=2008</samp> command-line 1039 1.1.1.14 mrg option. 1040 1.1.1.14 mrg </p></dd> 1041 1.1.1.6 mrg </dl> 1042 1.1.1.14 mrg <p>To use this configuration option you must have an assembler version 1043 1.1.1.14 mrg installed that supports the <samp>-mnan=</samp> command-line option too. 1044 1.1.1.6 mrg In the absence of this configuration option the default convention is 1045 1.1.1.14 mrg the legacy encoding, as when neither of the <samp>-mnan=2008</samp> and 1046 1.1.1.14 mrg <samp>-mnan=legacy</samp> command-line options has been used. 1047 1.1.1.14 mrg </p> 1048 1.1.1.14 mrg </dd> 1049 1.1.1.20 mrg <dt><span><code>--with-divide=<var>type</var></code></span></dt> 1050 1.1.1.14 mrg <dd><p>Specify how the compiler should generate code for checking for 1051 1.1.1.14 mrg division by zero. This option is only supported on the MIPS target. 1052 1.1 mrg The possibilities for <var>type</var> are: 1053 1.1.1.14 mrg </p><dl compact="compact"> 1054 1.1.1.20 mrg <dt><span><code>traps</code></span></dt> 1055 1.1.1.14 mrg <dd><p>Division by zero checks use conditional traps (this is the default on 1056 1.1.1.14 mrg systems that support conditional traps). 1057 1.1.1.14 mrg </p></dd> 1058 1.1.1.20 mrg <dt><span><code>breaks</code></span></dt> 1059 1.1.1.14 mrg <dd><p>Division by zero checks use the break instruction. 1060 1.1.1.14 mrg </p></dd> 1061 1.1 mrg </dl> 1062 1.1 mrg 1063 1.1.1.14 mrg 1064 1.1.1.14 mrg </dd> 1065 1.1.1.20 mrg <dt><span><code>--with-llsc</code></span></dt> 1066 1.1.1.14 mrg <dd><p>On MIPS targets, make <samp>-mllsc</samp> the default when no 1067 1.1.1.14 mrg <samp>-mno-llsc</samp> option is passed. This is the default for 1068 1.1 mrg Linux-based targets, as the kernel will emulate them if the ISA does 1069 1.1 mrg not provide them. 1070 1.1.1.14 mrg </p> 1071 1.1.1.14 mrg </dd> 1072 1.1.1.20 mrg <dt><span><code>--without-llsc</code></span></dt> 1073 1.1.1.14 mrg <dd><p>On MIPS targets, make <samp>-mno-llsc</samp> the default when no 1074 1.1.1.14 mrg <samp>-mllsc</samp> option is passed. 1075 1.1.1.14 mrg </p> 1076 1.1.1.14 mrg </dd> 1077 1.1.1.20 mrg <dt><span><code>--with-synci</code></span></dt> 1078 1.1.1.14 mrg <dd><p>On MIPS targets, make <samp>-msynci</samp> the default when no 1079 1.1.1.14 mrg <samp>-mno-synci</samp> option is passed. 1080 1.1.1.14 mrg </p> 1081 1.1.1.14 mrg </dd> 1082 1.1.1.20 mrg <dt><span><code>--without-synci</code></span></dt> 1083 1.1.1.14 mrg <dd><p>On MIPS targets, make <samp>-mno-synci</samp> the default when no 1084 1.1.1.14 mrg <samp>-msynci</samp> option is passed. This is the default. 1085 1.1.1.14 mrg </p> 1086 1.1.1.14 mrg </dd> 1087 1.1.1.20 mrg <dt><span><code>--with-lxc1-sxc1</code></span></dt> 1088 1.1.1.14 mrg <dd><p>On MIPS targets, make <samp>-mlxc1-sxc1</samp> the default when no 1089 1.1.1.14 mrg <samp>-mno-lxc1-sxc1</samp> option is passed. This is the default. 1090 1.1.1.14 mrg </p> 1091 1.1.1.14 mrg </dd> 1092 1.1.1.20 mrg <dt><span><code>--without-lxc1-sxc1</code></span></dt> 1093 1.1.1.14 mrg <dd><p>On MIPS targets, make <samp>-mno-lxc1-sxc1</samp> the default when no 1094 1.1.1.14 mrg <samp>-mlxc1-sxc1</samp> option is passed. The indexed load/store 1095 1.1.1.10 mrg instructions are not directly a problem but can lead to unexpected 1096 1.1.1.10 mrg behaviour when deployed in an application intended for a 32-bit address 1097 1.1.1.10 mrg space but run on a 64-bit processor. The issue is seen because all 1098 1.1.1.10 mrg known MIPS 64-bit Linux kernels execute o32 and n32 applications 1099 1.1.1.10 mrg with 64-bit addressing enabled which affects the overflow behaviour 1100 1.1.1.10 mrg of the indexed addressing mode. GCC will assume that ordinary 1101 1.1.1.10 mrg 32-bit arithmetic overflow behaviour is the same whether performed 1102 1.1.1.10 mrg as an <code>addu</code> instruction or as part of the address calculation 1103 1.1.1.10 mrg in <code>lwxc1</code> type instructions. This assumption holds true in a 1104 1.1.1.10 mrg pure 32-bit environment and can hold true in a 64-bit environment if 1105 1.1.1.10 mrg the address space is accurately set to be 32-bit for o32 and n32. 1106 1.1.1.14 mrg </p> 1107 1.1.1.14 mrg </dd> 1108 1.1.1.20 mrg <dt><span><code>--with-madd4</code></span></dt> 1109 1.1.1.14 mrg <dd><p>On MIPS targets, make <samp>-mmadd4</samp> the default when no 1110 1.1.1.14 mrg <samp>-mno-madd4</samp> option is passed. This is the default. 1111 1.1.1.14 mrg </p> 1112 1.1.1.14 mrg </dd> 1113 1.1.1.20 mrg <dt><span><code>--without-madd4</code></span></dt> 1114 1.1.1.14 mrg <dd><p>On MIPS targets, make <samp>-mno-madd4</samp> the default when no 1115 1.1.1.14 mrg <samp>-mmadd4</samp> option is passed. The <code>madd4</code> instruction 1116 1.1.1.10 mrg family can be problematic when targeting a combination of cores that 1117 1.1.1.10 mrg implement these instructions differently. There are two known cores 1118 1.1.1.10 mrg that implement these as fused operations instead of unfused (where 1119 1.1.1.10 mrg unfused is normally expected). Disabling these instructions is the 1120 1.1.1.10 mrg only way to ensure compatible code is generated; this will incur 1121 1.1.1.10 mrg a performance penalty. 1122 1.1.1.14 mrg </p> 1123 1.1.1.14 mrg </dd> 1124 1.1.1.20 mrg <dt><span><code>--with-mips-plt</code></span></dt> 1125 1.1.1.14 mrg <dd><p>On MIPS targets, make use of copy relocations and PLTs. 1126 1.1 mrg These features are extensions to the traditional 1127 1.1 mrg SVR4-based MIPS ABIs and require support from GNU binutils 1128 1.1 mrg and the runtime C library. 1129 1.1.1.14 mrg </p> 1130 1.1.1.14 mrg </dd> 1131 1.1.1.20 mrg <dt><span><code>--with-stack-clash-protection-guard-size=<var>size</var></code></span></dt> 1132 1.1.1.15 mrg <dd><p>On certain targets this option sets the default stack clash protection guard 1133 1.1.1.15 mrg size as a power of two in bytes. On AArch64 <var>size</var> is required to be either 1134 1.1.1.15 mrg 12 (4KB) or 16 (64KB). 1135 1.1.1.15 mrg </p> 1136 1.1.1.15 mrg </dd> 1137 1.1.1.20 mrg <dt><span><code>--with-isa-spec=<var>ISA-spec-string</var></code></span></dt> 1138 1.1.1.19 mrg <dd><p>On RISC-V targets specify the default version of the RISC-V Unprivileged 1139 1.1.1.19 mrg (formerly User-Level) ISA specification to produce code conforming to. 1140 1.1.1.19 mrg The possibilities for <var>ISA-spec-string</var> are: 1141 1.1.1.19 mrg </p><dl compact="compact"> 1142 1.1.1.20 mrg <dt><span><code>2.2</code></span></dt> 1143 1.1.1.19 mrg <dd><p>Produce code conforming to version 2.2. 1144 1.1.1.19 mrg </p></dd> 1145 1.1.1.20 mrg <dt><span><code>20190608</code></span></dt> 1146 1.1.1.19 mrg <dd><p>Produce code conforming to version 20190608. 1147 1.1.1.19 mrg </p></dd> 1148 1.1.1.20 mrg <dt><span><code>20191213</code></span></dt> 1149 1.1.1.19 mrg <dd><p>Produce code conforming to version 20191213. 1150 1.1.1.19 mrg </p></dd> 1151 1.1.1.19 mrg </dl> 1152 1.1.1.19 mrg <p>In the absence of this configuration option the default version is 20191213. 1153 1.1.1.19 mrg </p> 1154 1.1.1.19 mrg </dd> 1155 1.1.1.20 mrg <dt><span><code>--enable-__cxa_atexit</code></span></dt> 1156 1.1.1.14 mrg <dd><p>Define if you want to use __cxa_atexit, rather than atexit, to 1157 1.1.1.14 mrg register C++ destructors for local statics and global objects. 1158 1.1 mrg This is essential for fully standards-compliant handling of 1159 1.1 mrg destructors, but requires __cxa_atexit in libc. This option is currently 1160 1.1 mrg only available on systems with GNU libc. When enabled, this will cause 1161 1.1.1.14 mrg <samp>-fuse-cxa-atexit</samp> to be passed by default. 1162 1.1.1.14 mrg </p> 1163 1.1.1.14 mrg </dd> 1164 1.1.1.20 mrg <dt><span><code>--enable-gnu-indirect-function</code></span></dt> 1165 1.1.1.14 mrg <dd><p>Define if you want to enable the <code>ifunc</code> attribute. This option is 1166 1.1.1.3 skrll currently only available on systems with GNU libc on certain targets. 1167 1.1.1.14 mrg </p> 1168 1.1.1.14 mrg </dd> 1169 1.1.1.20 mrg <dt><span><code>--enable-target-optspace</code></span></dt> 1170 1.1.1.14 mrg <dd><p>Specify that target 1171 1.1.1.14 mrg libraries should be optimized for code space instead of code speed. 1172 1.1 mrg This is the default for the m32r platform. 1173 1.1.1.14 mrg </p> 1174 1.1.1.14 mrg </dd> 1175 1.1.1.20 mrg <dt><span><code>--with-cpp-install-dir=<var>dirname</var></code></span></dt> 1176 1.1.1.14 mrg <dd><p>Specify that the user visible <code>cpp</code> program should be installed 1177 1.1.1.14 mrg in <samp><var>prefix</var>/<var>dirname</var>/cpp</samp>, in addition to <var>bindir</var>. 1178 1.1.1.14 mrg </p> 1179 1.1.1.14 mrg </dd> 1180 1.1.1.20 mrg <dt><span><code>--enable-comdat</code></span></dt> 1181 1.1.1.14 mrg <dd><p>Enable COMDAT group support. This is primarily used to override the 1182 1.1 mrg automatically detected value. 1183 1.1.1.14 mrg </p> 1184 1.1.1.14 mrg </dd> 1185 1.1.1.20 mrg <dt><span><code>--enable-initfini-array</code></span></dt> 1186 1.1.1.14 mrg <dd><p>Force the use of sections <code>.init_array</code> and <code>.fini_array</code> 1187 1.1 mrg (instead of <code>.init</code> and <code>.fini</code>) for constructors and 1188 1.1.1.14 mrg destructors. Option <samp>--disable-initfini-array</samp> has the 1189 1.1 mrg opposite effect. If neither option is specified, the configure script 1190 1.1 mrg will try to guess whether the <code>.init_array</code> and 1191 1.1 mrg <code>.fini_array</code> sections are supported and, if they are, use them. 1192 1.1.1.14 mrg </p> 1193 1.1.1.14 mrg </dd> 1194 1.1.1.20 mrg <dt><span><code>--enable-link-mutex</code></span></dt> 1195 1.1.1.14 mrg <dd><p>When building GCC, use a mutex to avoid linking the compilers for 1196 1.1.1.6 mrg multiple languages at the same time, to avoid thrashing on build 1197 1.1.1.6 mrg systems with limited free memory. The default is not to use such a mutex. 1198 1.1.1.14 mrg </p> 1199 1.1.1.14 mrg </dd> 1200 1.1.1.20 mrg <dt><span><code>--enable-link-serialization</code></span></dt> 1201 1.1.1.19 mrg <dd><p>When building GCC, use make dependencies to serialize linking the compilers for 1202 1.1.1.19 mrg multiple languages, to avoid thrashing on build 1203 1.1.1.19 mrg systems with limited free memory. The default is not to add such 1204 1.1.1.19 mrg dependencies and thus with parallel make potentially link different 1205 1.1.1.19 mrg compilers concurrently. If the argument is a positive integer, allow 1206 1.1.1.19 mrg that number of concurrent link processes for the large binaries. 1207 1.1.1.19 mrg </p> 1208 1.1.1.19 mrg </dd> 1209 1.1.1.20 mrg <dt><span><code>--enable-maintainer-mode</code></span></dt> 1210 1.1.1.14 mrg <dd><p>The build rules that regenerate the Autoconf and Automake output files as 1211 1.1.1.14 mrg well as the GCC master message catalog <samp>gcc.pot</samp> are normally 1212 1.1 mrg disabled. This is because it can only be rebuilt if the complete source 1213 1.1 mrg tree is present. If you have changed the sources and want to rebuild the 1214 1.1.1.14 mrg catalog, configuring with <samp>--enable-maintainer-mode</samp> will enable 1215 1.1 mrg this. Note that you need a recent version of the <code>gettext</code> tools 1216 1.1 mrg to do so. 1217 1.1.1.14 mrg </p> 1218 1.1.1.14 mrg </dd> 1219 1.1.1.20 mrg <dt><span><code>--disable-bootstrap</code></span></dt> 1220 1.1.1.14 mrg <dd><p>For a native build, the default configuration is to perform 1221 1.1.1.14 mrg a 3-stage bootstrap of the compiler when ‘<samp>make</samp>’ is invoked, 1222 1.1 mrg testing that GCC can compile itself correctly. If you want to disable 1223 1.1.1.14 mrg this process, you can configure with <samp>--disable-bootstrap</samp>. 1224 1.1.1.14 mrg </p> 1225 1.1.1.14 mrg </dd> 1226 1.1.1.20 mrg <dt><span><code>--enable-bootstrap</code></span></dt> 1227 1.1.1.14 mrg <dd><p>In special cases, you may want to perform a 3-stage build 1228 1.1.1.14 mrg even if the target and host triplets are different. 1229 1.1 mrg This is possible when the host can run code compiled for 1230 1.1.1.14 mrg the target (e.g. host is i686-linux, target is i486-linux). 1231 1.1 mrg Starting from GCC 4.2, to do this you have to configure explicitly 1232 1.1.1.14 mrg with <samp>--enable-bootstrap</samp>. 1233 1.1.1.14 mrg </p> 1234 1.1.1.14 mrg </dd> 1235 1.1.1.20 mrg <dt><span><code>--enable-generated-files-in-srcdir</code></span></dt> 1236 1.1.1.14 mrg <dd><p>Neither the .c and .h files that are generated from Bison and flex nor the 1237 1.1 mrg info manuals and man pages that are built from the .texi files are present 1238 1.1.1.14 mrg in the repository development tree. When building GCC from that development tree, 1239 1.1 mrg or from one of our snapshots, those generated files are placed in your 1240 1.1 mrg build directory, which allows for the source to be in a readonly 1241 1.1 mrg directory. 1242 1.1.1.14 mrg </p> 1243 1.1.1.14 mrg <p>If you configure with <samp>--enable-generated-files-in-srcdir</samp> then those 1244 1.1 mrg generated files will go into the source directory. This is mainly intended 1245 1.1 mrg for generating release or prerelease tarballs of the GCC sources, since it 1246 1.1 mrg is not a requirement that the users of source releases to have flex, Bison, 1247 1.1 mrg or makeinfo. 1248 1.1.1.14 mrg </p> 1249 1.1.1.14 mrg </dd> 1250 1.1.1.20 mrg <dt><span><code>--enable-version-specific-runtime-libs</code></span></dt> 1251 1.1.1.14 mrg <dd><p>Specify 1252 1.1 mrg that runtime libraries should be installed in the compiler specific 1253 1.1.1.14 mrg subdirectory (<samp><var>libdir</var>/gcc</samp>) rather than the usual places. In 1254 1.1.1.14 mrg addition, ‘<samp>libstdc++</samp>’’s include files will be installed into 1255 1.1 mrg <samp><var>libdir</var></samp> unless you overruled it by using 1256 1.1.1.14 mrg <samp>--with-gxx-include-dir=<var>dirname</var></samp>. Using this option is 1257 1.1 mrg particularly useful if you intend to use several versions of GCC in 1258 1.1.1.16 mrg parallel. The default is ‘<samp>yes</samp>’ for ‘<samp>libada</samp>’, and ‘<samp>no</samp>’ for 1259 1.1.1.16 mrg the remaining libraries. 1260 1.1.1.14 mrg </p> 1261 1.1.1.14 mrg </dd> 1262 1.1.1.20 mrg <dt><span><code><span id="WithAixSoname"></span>--with-aix-soname=‘<samp>aix</samp>’, ‘<samp>svr4</samp>’ or ‘<samp>both</samp>’</code></span></dt> 1263 1.1.1.14 mrg <dd><p>Traditional AIX shared library versioning (versioned <code>Shared Object</code> 1264 1.1.1.6 mrg files as members of unversioned <code>Archive Library</code> files named 1265 1.1.1.14 mrg ‘<samp>lib.a</samp>’) causes numerous headaches for package managers. However, 1266 1.1.1.6 mrg <code>Import Files</code> as members of <code>Archive Library</code> files allow for 1267 1.1.1.6 mrg <strong>filename-based versioning</strong> of shared libraries as seen on Linux/SVR4, 1268 1.1.1.14 mrg where this is called the "SONAME". But as they prevent static linking, 1269 1.1.1.6 mrg <code>Import Files</code> may be used with <code>Runtime Linking</code> only, where the 1270 1.1.1.14 mrg linker does search for ‘<samp>libNAME.so</samp>’ before ‘<samp>libNAME.a</samp>’ library 1271 1.1.1.14 mrg filenames with the ‘<samp>-lNAME</samp>’ linker flag. 1272 1.1.1.14 mrg </p> 1273 1.1.1.20 mrg <span id="AixLdCommand"></span><p>For detailed information please refer to the AIX 1274 1.1.1.14 mrg <a href="https://www.ibm.com/support/knowledgecenter/search/%22the%20ld%20command%2C%20also%20called%20the%20linkage%20editor%20or%20binder%22">ld 1275 1.1.1.14 mrg Command</a> reference. 1276 1.1.1.14 mrg </p> 1277 1.1.1.14 mrg <p>As long as shared library creation is enabled, upon: 1278 1.1.1.14 mrg </p><dl compact="compact"> 1279 1.1.1.20 mrg <dt><span><code>--with-aix-soname=aix</code></span></dt> 1280 1.1.1.20 mrg <dt><span><code>--with-aix-soname=both</code></span></dt> 1281 1.1.1.14 mrg <dd><p>A (traditional AIX) <code>Shared Archive Library</code> file is created: 1282 1.1.1.14 mrg </p><ul> 1283 1.1.1.14 mrg <li> using the ‘<samp>libNAME.a</samp>’ filename scheme 1284 1.1.1.14 mrg </li><li> with the <code>Shared Object</code> file as archive member named 1285 1.1.1.14 mrg ‘<samp>libNAME.so.V</samp>’ (except for ‘<samp>libgcc_s</samp>’, where the <code>Shared 1286 1.1.1.14 mrg Object</code> file is named ‘<samp>shr.o</samp>’ for backwards compatibility), which 1287 1.1.1.14 mrg <ul class="no-bullet"> 1288 1.1.1.14 mrg <li>- is used for runtime loading from inside the ‘<samp>libNAME.a</samp>’ file 1289 1.1.1.14 mrg </li><li>- is used for dynamic loading via 1290 1.1.1.14 mrg <code>dlopen("libNAME.a(libNAME.so.V)", RTLD_MEMBER)</code> 1291 1.1.1.14 mrg </li><li>- is used for shared linking 1292 1.1.1.14 mrg </li><li>- is used for static linking, so no separate <code>Static Archive 1293 1.1.1.6 mrg Library</code> file is needed 1294 1.1.1.14 mrg </li></ul> 1295 1.1.1.14 mrg </li></ul> 1296 1.1.1.14 mrg </dd> 1297 1.1.1.20 mrg <dt><span><code>--with-aix-soname=both</code></span></dt> 1298 1.1.1.20 mrg <dt><span><code>--with-aix-soname=svr4</code></span></dt> 1299 1.1.1.14 mrg <dd><p>A (second) <code>Shared Archive Library</code> file is created: 1300 1.1.1.14 mrg </p><ul> 1301 1.1.1.14 mrg <li> using the ‘<samp>libNAME.so.V</samp>’ filename scheme 1302 1.1.1.14 mrg </li><li> with the <code>Shared Object</code> file as archive member named 1303 1.1.1.14 mrg ‘<samp>shr.o</samp>’, which 1304 1.1.1.14 mrg <ul class="no-bullet"> 1305 1.1.1.14 mrg <li>- is created with the <code>-G linker flag</code> 1306 1.1.1.14 mrg </li><li>- has the <code>F_LOADONLY</code> flag set 1307 1.1.1.14 mrg </li><li>- is used for runtime loading from inside the ‘<samp>libNAME.so.V</samp>’ file 1308 1.1.1.14 mrg </li><li>- is used for dynamic loading via <code>dlopen("libNAME.so.V(shr.o)", 1309 1.1.1.6 mrg RTLD_MEMBER)</code> 1310 1.1.1.14 mrg </li></ul> 1311 1.1.1.14 mrg </li><li> with the <code>Import File</code> as archive member named ‘<samp>shr.imp</samp>’, 1312 1.1.1.6 mrg which 1313 1.1.1.14 mrg <ul class="no-bullet"> 1314 1.1.1.14 mrg <li>- refers to ‘<samp>libNAME.so.V(shr.o)</samp>’ as the "SONAME", to be recorded 1315 1.1.1.6 mrg in the <code>Loader Section</code> of subsequent binaries 1316 1.1.1.14 mrg </li><li>- indicates whether ‘<samp>libNAME.so.V(shr.o)</samp>’ is 32 or 64 bit 1317 1.1.1.14 mrg </li><li>- lists all the public symbols exported by ‘<samp>lib.so.V(shr.o)</samp>’, 1318 1.1.1.14 mrg eventually decorated with the <code>‘<samp>weak</samp>’ Keyword</code> 1319 1.1.1.14 mrg </li><li>- is necessary for shared linking against ‘<samp>lib.so.V(shr.o)</samp>’ 1320 1.1.1.14 mrg </li></ul> 1321 1.1.1.14 mrg </li></ul> 1322 1.1.1.14 mrg <p>A symbolic link using the ‘<samp>libNAME.so</samp>’ filename scheme is created: 1323 1.1.1.14 mrg </p><ul> 1324 1.1.1.14 mrg <li> pointing to the ‘<samp>libNAME.so.V</samp>’ <code>Shared Archive Library</code> file 1325 1.1.1.14 mrg </li><li> to permit the <code>ld Command</code> to find ‘<samp>lib.so.V(shr.imp)</samp>’ via 1326 1.1.1.14 mrg the ‘<samp>-lNAME</samp>’ argument (requires <code>Runtime Linking</code> to be enabled) 1327 1.1.1.14 mrg </li><li> to permit dynamic loading of ‘<samp>lib.so.V(shr.o)</samp>’ without the need 1328 1.1.1.14 mrg to specify the version number via <code>dlopen("libNAME.so(shr.o)", 1329 1.1.1.6 mrg RTLD_MEMBER)</code> 1330 1.1.1.14 mrg </li></ul> 1331 1.1.1.14 mrg </dd> 1332 1.1.1.14 mrg </dl> 1333 1.1.1.6 mrg 1334 1.1.1.14 mrg <p>As long as static library creation is enabled, upon: 1335 1.1.1.14 mrg </p><dl compact="compact"> 1336 1.1.1.20 mrg <dt><span><code>--with-aix-soname=svr4</code></span></dt> 1337 1.1.1.14 mrg <dd><p>A <code>Static Archive Library</code> is created: 1338 1.1.1.14 mrg </p><ul> 1339 1.1.1.14 mrg <li> using the ‘<samp>libNAME.a</samp>’ filename scheme 1340 1.1.1.14 mrg </li><li> with all the <code>Static Object</code> files as archive members, which 1341 1.1.1.14 mrg <ul class="no-bullet"> 1342 1.1.1.14 mrg <li>- are used for static linking 1343 1.1.1.14 mrg </li></ul> 1344 1.1.1.14 mrg </li></ul> 1345 1.1.1.14 mrg </dd> 1346 1.1.1.14 mrg </dl> 1347 1.1.1.6 mrg 1348 1.1.1.14 mrg <p>While the aix-soname=‘<samp>svr4</samp>’ option does not create <code>Shared Object</code> 1349 1.1.1.6 mrg files as members of unversioned <code>Archive Library</code> files any more, package 1350 1.1.1.6 mrg managers still are responsible to 1351 1.1.1.6 mrg <a href="./specific.html#TransferAixShobj">transfer</a> <code>Shared Object</code> files 1352 1.1.1.6 mrg found as member of a previously installed unversioned <code>Archive Library</code> 1353 1.1.1.6 mrg file into the newly installed <code>Archive Library</code> file with the same 1354 1.1.1.6 mrg filename. 1355 1.1.1.14 mrg </p> 1356 1.1.1.14 mrg <p><em>WARNING:</em> Creating <code>Shared Object</code> files with <code>Runtime Linking</code> 1357 1.1.1.6 mrg enabled may bloat the TOC, eventually leading to <code>TOC overflow</code> errors, 1358 1.1.1.14 mrg requiring the use of either the <samp>-Wl,-bbigtoc</samp> linker flag (seen to 1359 1.1.1.6 mrg break with the <code>GDB</code> debugger) or some of the TOC-related compiler flags, 1360 1.1.1.6 mrg see “RS/6000 and PowerPC Options” in the main manual. 1361 1.1.1.14 mrg </p> 1362 1.1.1.14 mrg <p><samp>--with-aix-soname</samp> is currently supported by ‘<samp>libgcc_s</samp>’ only, so 1363 1.1.1.6 mrg this option is still experimental and not for normal use yet. 1364 1.1.1.14 mrg </p> 1365 1.1.1.14 mrg <p>Default is the traditional behavior <samp>--with-aix-soname=‘<samp>aix</samp>’</samp>. 1366 1.1.1.14 mrg </p> 1367 1.1.1.14 mrg </dd> 1368 1.1.1.20 mrg <dt><span><code>--enable-languages=<var>lang1</var>,<var>lang2</var>,…</code></span></dt> 1369 1.1.1.14 mrg <dd><p>Specify that only a particular subset of compilers and 1370 1.1 mrg their runtime libraries should be built. For a list of valid values for 1371 1.1 mrg <var>langN</var> you can issue the following command in the 1372 1.1.1.14 mrg <samp>gcc</samp> directory of your GCC source tree:<br> 1373 1.1.1.20 mrg </p><div class="example"> 1374 1.1.1.20 mrg <pre class="example">grep ^language= */config-lang.in 1375 1.1.1.14 mrg </pre></div> 1376 1.1.1.14 mrg <p>Currently, you can use any of the following: 1377 1.1.1.15 mrg <code>all</code>, <code>default</code>, <code>ada</code>, <code>c</code>, <code>c++</code>, <code>d</code>, 1378 1.1.1.15 mrg <code>fortran</code>, <code>go</code>, <code>jit</code>, <code>lto</code>, <code>objc</code>, <code>obj-c++</code>. 1379 1.1.1.14 mrg Building the Ada compiler has special requirements, see below. 1380 1.1.1.14 mrg If you do not pass this flag, or specify the option <code>default</code>, then the 1381 1.1.1.14 mrg default languages available in the <samp>gcc</samp> sub-tree will be configured. 1382 1.1.1.15 mrg Ada, D, Go, Jit, and Objective-C++ are not default languages. LTO is not a 1383 1.1.1.14 mrg default language, but is built by default because <samp>--enable-lto</samp> is 1384 1.1.1.14 mrg enabled by default. The other languages are default languages. If 1385 1.1.1.14 mrg <code>all</code> is specified, then all available languages are built. An 1386 1.1.1.14 mrg exception is <code>jit</code> language, which requires 1387 1.1.1.14 mrg <samp>--enable-host-shared</samp> to be included with <code>all</code>. 1388 1.1.1.14 mrg </p> 1389 1.1.1.14 mrg </dd> 1390 1.1.1.20 mrg <dt><span><code>--enable-stage1-languages=<var>lang1</var>,<var>lang2</var>,…</code></span></dt> 1391 1.1.1.14 mrg <dd><p>Specify that a particular subset of compilers and their runtime 1392 1.1 mrg libraries should be built with the system C compiler during stage 1 of 1393 1.1 mrg the bootstrap process, rather than only in later stages with the 1394 1.1 mrg bootstrapped C compiler. The list of valid values is the same as for 1395 1.1.1.14 mrg <samp>--enable-languages</samp>, and the option <code>all</code> will select all 1396 1.1.1.14 mrg of the languages enabled by <samp>--enable-languages</samp>. This option is 1397 1.1 mrg primarily useful for GCC development; for instance, when a development 1398 1.1 mrg version of the compiler cannot bootstrap due to compiler bugs, or when 1399 1.1 mrg one is debugging front ends other than the C front end. When this 1400 1.1 mrg option is used, one can then build the target libraries for the 1401 1.1.1.14 mrg specified languages with the stage-1 compiler by using <code>make 1402 1.1.1.14 mrg stage1-bubble all-target</code>, or run the testsuite on the stage-1 compiler 1403 1.1.1.14 mrg for the specified languages using <code>make stage1-start check-gcc</code>. 1404 1.1.1.14 mrg </p> 1405 1.1.1.14 mrg </dd> 1406 1.1.1.20 mrg <dt><span><code>--disable-libada</code></span></dt> 1407 1.1.1.14 mrg <dd><p>Specify that the run-time libraries and tools used by GNAT should not 1408 1.1 mrg be built. This can be useful for debugging, or for compatibility with 1409 1.1 mrg previous Ada build procedures, when it was required to explicitly 1410 1.1.1.14 mrg do a ‘<samp>make -C gcc gnatlib_and_tools</samp>’. 1411 1.1.1.14 mrg </p> 1412 1.1.1.14 mrg </dd> 1413 1.1.1.20 mrg <dt><span><code>--disable-libsanitizer</code></span></dt> 1414 1.1.1.14 mrg <dd><p>Specify that the run-time libraries for the various sanitizers should 1415 1.1.1.6 mrg not be built. 1416 1.1.1.14 mrg </p> 1417 1.1.1.14 mrg </dd> 1418 1.1.1.20 mrg <dt><span><code>--disable-libssp</code></span></dt> 1419 1.1.1.14 mrg <dd><p>Specify that the run-time libraries for stack smashing protection 1420 1.1.1.14 mrg should not be built or linked against. On many targets library support 1421 1.1.1.14 mrg is provided by the C library instead. 1422 1.1.1.14 mrg </p> 1423 1.1.1.14 mrg </dd> 1424 1.1.1.20 mrg <dt><span><code>--disable-libquadmath</code></span></dt> 1425 1.1.1.14 mrg <dd><p>Specify that the GCC quad-precision math library should not be built. 1426 1.1.1.3 skrll On some systems, the library is required to be linkable when building 1427 1.1.1.14 mrg the Fortran front end, unless <samp>--disable-libquadmath-support</samp> 1428 1.1.1.3 skrll is used. 1429 1.1.1.14 mrg </p> 1430 1.1.1.14 mrg </dd> 1431 1.1.1.20 mrg <dt><span><code>--disable-libquadmath-support</code></span></dt> 1432 1.1.1.14 mrg <dd><p>Specify that the Fortran front end and <code>libgfortran</code> do not add 1433 1.1.1.3 skrll support for <code>libquadmath</code> on systems supporting it. 1434 1.1.1.14 mrg </p> 1435 1.1.1.14 mrg </dd> 1436 1.1.1.20 mrg <dt><span><code>--disable-libgomp</code></span></dt> 1437 1.1.1.14 mrg <dd><p>Specify that the GNU Offloading and Multi Processing Runtime Library 1438 1.1.1.6 mrg should not be built. 1439 1.1.1.14 mrg </p> 1440 1.1.1.14 mrg </dd> 1441 1.1.1.20 mrg <dt><span><code>--disable-libvtv</code></span></dt> 1442 1.1.1.14 mrg <dd><p>Specify that the run-time libraries used by vtable verification 1443 1.1.1.6 mrg should not be built. 1444 1.1.1.14 mrg </p> 1445 1.1.1.14 mrg </dd> 1446 1.1.1.20 mrg <dt><span><code>--with-dwarf2</code></span></dt> 1447 1.1.1.14 mrg <dd><p>Specify that the compiler should 1448 1.1 mrg use DWARF 2 debugging information as the default. 1449 1.1.1.14 mrg </p> 1450 1.1.1.14 mrg </dd> 1451 1.1.1.20 mrg <dt><span><code>--with-advance-toolchain=<var>at</var></code></span></dt> 1452 1.1.1.14 mrg <dd><p>On 64-bit PowerPC Linux systems, configure the compiler to use the 1453 1.1.1.8 mrg header files, library files, and the dynamic linker from the Advance 1454 1.1.1.8 mrg Toolchain release <var>at</var> instead of the default versions that are 1455 1.1.1.8 mrg provided by the Linux distribution. In general, this option is 1456 1.1.1.8 mrg intended for the developers of GCC, and it is not intended for general 1457 1.1.1.8 mrg use. 1458 1.1.1.14 mrg </p> 1459 1.1.1.14 mrg </dd> 1460 1.1.1.20 mrg <dt><span><code>--enable-targets=all</code></span></dt> 1461 1.1.1.20 mrg <dt><span><code>--enable-targets=<var>target_list</var></code></span></dt> 1462 1.1.1.14 mrg <dd><p>Some GCC targets, e.g. powerpc64-linux, build bi-arch compilers. 1463 1.1 mrg These are compilers that are able to generate either 64-bit or 32-bit 1464 1.1.1.14 mrg code. Typically, the corresponding 32-bit target, e.g. 1465 1.1 mrg powerpc-linux for powerpc64-linux, only generates 32-bit code. This 1466 1.1 mrg option enables the 32-bit target to be a bi-arch compiler, which is 1467 1.1 mrg useful when you want a bi-arch compiler that defaults to 32-bit, and 1468 1.1.1.14 mrg you are building a bi-arch or multi-arch binutils in a combined tree. 1469 1.1 mrg On mips-linux, this will build a tri-arch compiler (ABI o32/n32/64), 1470 1.1.1.14 mrg defaulted to o32. 1471 1.1.1.3 skrll Currently, this option only affects sparc-linux, powerpc-linux, x86-linux, 1472 1.1.1.3 skrll mips-linux and s390-linux. 1473 1.1.1.14 mrg </p> 1474 1.1.1.14 mrg </dd> 1475 1.1.1.20 mrg <dt><span><code>--enable-default-pie</code></span></dt> 1476 1.1.1.14 mrg <dd><p>Turn on <samp>-fPIE</samp> and <samp>-pie</samp> by default. 1477 1.1.1.14 mrg </p> 1478 1.1.1.14 mrg </dd> 1479 1.1.1.20 mrg <dt><span><code>--enable-secureplt</code></span></dt> 1480 1.1.1.14 mrg <dd><p>This option enables <samp>-msecure-plt</samp> by default for powerpc-linux. 1481 1.1 mrg See “RS/6000 and PowerPC Options” in the main manual 1482 1.1.1.14 mrg </p> 1483 1.1.1.14 mrg </dd> 1484 1.1.1.20 mrg <dt><span><code>--enable-default-ssp</code></span></dt> 1485 1.1.1.14 mrg <dd><p>Turn on <samp>-fstack-protector-strong</samp> by default. 1486 1.1.1.14 mrg </p> 1487 1.1.1.14 mrg </dd> 1488 1.1.1.20 mrg <dt><span><code>--enable-cld</code></span></dt> 1489 1.1.1.14 mrg <dd><p>This option enables <samp>-mcld</samp> by default for 32-bit x86 targets. 1490 1.1 mrg See “i386 and x86-64 Options” in the main manual 1491 1.1.1.14 mrg </p> 1492 1.1.1.14 mrg </dd> 1493 1.1.1.20 mrg <dt><span><code>--enable-large-address-aware</code></span></dt> 1494 1.1.1.15 mrg <dd><p>The <samp>--enable-large-address-aware</samp> option arranges for MinGW 1495 1.1.1.15 mrg executables to be linked using the <samp>--large-address-aware</samp> 1496 1.1.1.15 mrg option, that enables the use of more than 2GB of memory. If GCC is 1497 1.1.1.15 mrg configured with this option, its effects can be reversed by passing the 1498 1.1.1.15 mrg <samp>-Wl,--disable-large-address-aware</samp> option to the so-configured 1499 1.1.1.15 mrg compiler driver. 1500 1.1.1.15 mrg </p> 1501 1.1.1.15 mrg </dd> 1502 1.1.1.20 mrg <dt><span><code>--enable-win32-registry</code></span></dt> 1503 1.1.1.20 mrg <dt><span><code>--enable-win32-registry=<var>key</var></code></span></dt> 1504 1.1.1.20 mrg <dt><span><code>--disable-win32-registry</code></span></dt> 1505 1.1.1.14 mrg <dd><p>The <samp>--enable-win32-registry</samp> option enables Microsoft Windows-hosted GCC 1506 1.1 mrg to look up installations paths in the registry using the following key: 1507 1.1.1.14 mrg </p> 1508 1.1.1.20 mrg <div class="example"> 1509 1.1.1.20 mrg <pre class="example"><code>HKEY_LOCAL_MACHINE\SOFTWARE\Free Software Foundation\<var>key</var></code> 1510 1.1.1.14 mrg </pre></div> 1511 1.1 mrg 1512 1.1.1.14 mrg <p><var>key</var> defaults to GCC version number, and can be overridden by the 1513 1.1.1.14 mrg <samp>--enable-win32-registry=<var>key</var></samp> option. Vendors and distributors 1514 1.1 mrg who use custom installers are encouraged to provide a different key, 1515 1.1 mrg perhaps one comprised of vendor name and GCC version number, to 1516 1.1 mrg avoid conflict with existing installations. This feature is enabled 1517 1.1.1.14 mrg by default, and can be disabled by <samp>--disable-win32-registry</samp> 1518 1.1 mrg option. This option has no effect on the other hosts. 1519 1.1.1.14 mrg </p> 1520 1.1.1.14 mrg </dd> 1521 1.1.1.20 mrg <dt><span><code>--nfp</code></span></dt> 1522 1.1.1.14 mrg <dd><p>Specify that the machine does not have a floating point unit. This 1523 1.1.1.14 mrg option only applies to ‘<samp>m68k-sun-sunos<var>n</var></samp>’. On any other 1524 1.1.1.14 mrg system, <samp>--nfp</samp> has no effect. 1525 1.1.1.14 mrg </p> 1526 1.1.1.14 mrg </dd> 1527 1.1.1.20 mrg <dt><span><code>--enable-werror</code></span></dt> 1528 1.1.1.20 mrg <dt><span><code>--disable-werror</code></span></dt> 1529 1.1.1.20 mrg <dt><span><code>--enable-werror=yes</code></span></dt> 1530 1.1.1.20 mrg <dt><span><code>--enable-werror=no</code></span></dt> 1531 1.1.1.14 mrg <dd><p>When you specify this option, it controls whether certain files in the 1532 1.1.1.14 mrg compiler are built with <samp>-Werror</samp> in bootstrap stage2 and later. 1533 1.1.1.14 mrg If you don’t specify it, <samp>-Werror</samp> is turned on for the main 1534 1.1 mrg development trunk. However it defaults to off for release branches and 1535 1.1.1.14 mrg final releases. The specific files which get <samp>-Werror</samp> are 1536 1.1 mrg controlled by the Makefiles. 1537 1.1.1.14 mrg </p> 1538 1.1.1.14 mrg </dd> 1539 1.1.1.20 mrg <dt><span><code>--enable-checking</code></span></dt> 1540 1.1.1.20 mrg <dt><span><code>--disable-checking</code></span></dt> 1541 1.1.1.20 mrg <dt><span><code>--enable-checking=<var>list</var></code></span></dt> 1542 1.1.1.14 mrg <dd><p>This option controls performing internal consistency checks in the compiler. 1543 1.1.1.14 mrg It does not change the generated code, but adds error checking of the 1544 1.1.1.14 mrg requested complexity. This slows down the compiler and may only work 1545 1.1.1.14 mrg properly if you are building the compiler with GCC. 1546 1.1.1.14 mrg </p> 1547 1.1.1.14 mrg <p>When the option is not specified, the active set of checks depends on context. 1548 1.1.1.14 mrg Namely, bootstrap stage 1 defaults to ‘<samp>--enable-checking=yes</samp>’, builds 1549 1.1.1.14 mrg from release branches or release archives default to 1550 1.1.1.14 mrg ‘<samp>--enable-checking=release</samp>’, and otherwise 1551 1.1.1.14 mrg ‘<samp>--enable-checking=yes,extra</samp>’ is used. When the option is 1552 1.1.1.14 mrg specified without a <var>list</var>, the result is the same as 1553 1.1.1.14 mrg ‘<samp>--enable-checking=yes</samp>’. Likewise, ‘<samp>--disable-checking</samp>’ is 1554 1.1.1.14 mrg equivalent to ‘<samp>--enable-checking=no</samp>’. 1555 1.1.1.14 mrg </p> 1556 1.1.1.14 mrg <p>The categories of checks available in <var>list</var> are ‘<samp>yes</samp>’ (most common 1557 1.1.1.14 mrg checks ‘<samp>assert,misc,gc,gimple,rtlflag,runtime,tree,types</samp>’), ‘<samp>no</samp>’ 1558 1.1.1.14 mrg (no checks at all), ‘<samp>all</samp>’ (all but ‘<samp>valgrind</samp>’), ‘<samp>release</samp>’ 1559 1.1.1.14 mrg (cheapest checks ‘<samp>assert,runtime</samp>’) or ‘<samp>none</samp>’ (same as ‘<samp>no</samp>’). 1560 1.1.1.14 mrg ‘<samp>release</samp>’ checks are always on and to disable them 1561 1.1.1.14 mrg ‘<samp>--disable-checking</samp>’ or ‘<samp>--enable-checking=no[,<other checks>]</samp>’ 1562 1.1.1.14 mrg must be explicitly requested. Disabling assertions makes the compiler and 1563 1.1.1.14 mrg runtime slightly faster but increases the risk of undetected internal errors 1564 1.1.1.14 mrg causing wrong code to be generated. 1565 1.1.1.14 mrg </p> 1566 1.1.1.14 mrg <p>Individual checks can be enabled with these flags: ‘<samp>assert</samp>’, ‘<samp>df</samp>’, 1567 1.1.1.14 mrg ‘<samp>extra</samp>’, ‘<samp>fold</samp>’, ‘<samp>gc</samp>’, ‘<samp>gcac</samp>’, ‘<samp>gimple</samp>’, 1568 1.1.1.14 mrg ‘<samp>misc</samp>’, ‘<samp>rtl</samp>’, ‘<samp>rtlflag</samp>’, ‘<samp>runtime</samp>’, ‘<samp>tree</samp>’, 1569 1.1.1.14 mrg ‘<samp>types</samp>’ and ‘<samp>valgrind</samp>’. ‘<samp>extra</samp>’ extends ‘<samp>misc</samp>’ 1570 1.1.1.14 mrg checking with extra checks that might affect code generation and should 1571 1.1.1.14 mrg therefore not differ between stage1 and later stages in bootstrap. 1572 1.1.1.14 mrg </p> 1573 1.1.1.14 mrg <p>The ‘<samp>valgrind</samp>’ check requires the external <code>valgrind</code> simulator, 1574 1.1.1.19 mrg available from <a href="https://valgrind.org">https://valgrind.org</a>. The ‘<samp>rtl</samp>’ checks are 1575 1.1.1.14 mrg expensive and the ‘<samp>df</samp>’, ‘<samp>gcac</samp>’ and ‘<samp>valgrind</samp>’ checks are very 1576 1.1.1.14 mrg expensive. 1577 1.1.1.14 mrg </p> 1578 1.1.1.14 mrg </dd> 1579 1.1.1.20 mrg <dt><span><code>--disable-stage1-checking</code></span></dt> 1580 1.1.1.20 mrg <dt><span><code>--enable-stage1-checking</code></span></dt> 1581 1.1.1.20 mrg <dt><span><code>--enable-stage1-checking=<var>list</var></code></span></dt> 1582 1.1.1.14 mrg <dd><p>This option affects only bootstrap build. If no <samp>--enable-checking</samp> 1583 1.1.1.14 mrg option is specified the stage1 compiler is built with ‘<samp>yes</samp>’ checking 1584 1.1.1.14 mrg enabled, otherwise the stage1 checking flags are the same as specified by 1585 1.1.1.14 mrg <samp>--enable-checking</samp>. To build the stage1 compiler with 1586 1.1.1.14 mrg different checking options use <samp>--enable-stage1-checking</samp>. 1587 1.1.1.14 mrg The list of checking options is the same as for <samp>--enable-checking</samp>. 1588 1.1 mrg If your system is too slow or too small to bootstrap a released compiler 1589 1.1.1.14 mrg with checking for stage1 enabled, you can use ‘<samp>--disable-stage1-checking</samp>’ 1590 1.1 mrg to disable checking for the stage1 compiler. 1591 1.1.1.14 mrg </p> 1592 1.1.1.14 mrg </dd> 1593 1.1.1.20 mrg <dt><span><code>--enable-coverage</code></span></dt> 1594 1.1.1.20 mrg <dt><span><code>--enable-coverage=<var>level</var></code></span></dt> 1595 1.1.1.14 mrg <dd><p>With this option, the compiler is built to collect self coverage 1596 1.1 mrg information, every time it is run. This is for internal development 1597 1.1 mrg purposes, and only works when the compiler is being built with gcc. The 1598 1.1 mrg <var>level</var> argument controls whether the compiler is built optimized or 1599 1.1.1.14 mrg not, values are ‘<samp>opt</samp>’ and ‘<samp>noopt</samp>’. For coverage analysis you 1600 1.1 mrg want to disable optimization, for performance analysis you want to 1601 1.1 mrg enable optimization. When coverage is enabled, the default level is 1602 1.1 mrg without optimization. 1603 1.1.1.14 mrg </p> 1604 1.1.1.14 mrg </dd> 1605 1.1.1.20 mrg <dt><span><code>--enable-gather-detailed-mem-stats</code></span></dt> 1606 1.1.1.14 mrg <dd><p>When this option is specified more detailed information on memory 1607 1.1 mrg allocation is gathered. This information is printed when using 1608 1.1.1.14 mrg <samp>-fmem-report</samp>. 1609 1.1.1.14 mrg </p> 1610 1.1.1.14 mrg </dd> 1611 1.1.1.20 mrg <dt><span><code>--enable-valgrind-annotations</code></span></dt> 1612 1.1.1.14 mrg <dd><p>Mark selected memory related operations in the compiler when run under 1613 1.1.1.8 mrg valgrind to suppress false positives. 1614 1.1.1.14 mrg </p> 1615 1.1.1.14 mrg </dd> 1616 1.1.1.20 mrg <dt><span><code>--enable-nls</code></span></dt> 1617 1.1.1.20 mrg <dt><span><code>--disable-nls</code></span></dt> 1618 1.1.1.14 mrg <dd><p>The <samp>--enable-nls</samp> option enables Native Language Support (NLS), 1619 1.1 mrg which lets GCC output diagnostics in languages other than American 1620 1.1 mrg English. Native Language Support is enabled by default if not doing a 1621 1.1.1.14 mrg canadian cross build. The <samp>--disable-nls</samp> option disables NLS. 1622 1.1.1.14 mrg </p> 1623 1.1.1.14 mrg </dd> 1624 1.1.1.20 mrg <dt><span><code>--with-included-gettext</code></span></dt> 1625 1.1.1.14 mrg <dd><p>If NLS is enabled, the <samp>--with-included-gettext</samp> option causes the build 1626 1.1.1.14 mrg procedure to prefer its copy of GNU <code>gettext</code>. 1627 1.1.1.14 mrg </p> 1628 1.1.1.14 mrg </dd> 1629 1.1.1.20 mrg <dt><span><code>--with-catgets</code></span></dt> 1630 1.1.1.14 mrg <dd><p>If NLS is enabled, and if the host lacks <code>gettext</code> but has the 1631 1.1 mrg inferior <code>catgets</code> interface, the GCC build procedure normally 1632 1.1.1.14 mrg ignores <code>catgets</code> and instead uses GCC’s copy of the GNU 1633 1.1.1.14 mrg <code>gettext</code> library. The <samp>--with-catgets</samp> option causes the 1634 1.1.1.14 mrg build procedure to use the host’s <code>catgets</code> in this situation. 1635 1.1.1.14 mrg </p> 1636 1.1.1.14 mrg </dd> 1637 1.1.1.20 mrg <dt><span><code>--with-libiconv-prefix=<var>dir</var></code></span></dt> 1638 1.1.1.14 mrg <dd><p>Search for libiconv header files in <samp><var>dir</var>/include</samp> and 1639 1.1.1.14 mrg libiconv library files in <samp><var>dir</var>/lib</samp>. 1640 1.1.1.14 mrg </p> 1641 1.1.1.14 mrg </dd> 1642 1.1.1.20 mrg <dt><span><code>--enable-obsolete</code></span></dt> 1643 1.1.1.14 mrg <dd><p>Enable configuration for an obsoleted system. If you attempt to 1644 1.1 mrg configure GCC for a system (build, host, or target) which has been 1645 1.1 mrg obsoleted, and you do not specify this flag, configure will halt with an 1646 1.1 mrg error message. 1647 1.1.1.14 mrg </p> 1648 1.1.1.14 mrg <p>All support for systems which have been obsoleted in one release of GCC 1649 1.1 mrg is removed entirely in the next major release, unless someone steps 1650 1.1 mrg forward to maintain the port. 1651 1.1.1.14 mrg </p> 1652 1.1.1.14 mrg </dd> 1653 1.1.1.20 mrg <dt><span><code>--enable-decimal-float</code></span></dt> 1654 1.1.1.20 mrg <dt><span><code>--enable-decimal-float=yes</code></span></dt> 1655 1.1.1.20 mrg <dt><span><code>--enable-decimal-float=no</code></span></dt> 1656 1.1.1.20 mrg <dt><span><code>--enable-decimal-float=bid</code></span></dt> 1657 1.1.1.20 mrg <dt><span><code>--enable-decimal-float=dpd</code></span></dt> 1658 1.1.1.20 mrg <dt><span><code>--disable-decimal-float</code></span></dt> 1659 1.1.1.14 mrg <dd><p>Enable (or disable) support for the C decimal floating point extension 1660 1.1 mrg that is in the IEEE 754-2008 standard. This is enabled by default only 1661 1.1 mrg on PowerPC, i386, and x86_64 GNU/Linux systems. Other systems may also 1662 1.1 mrg support it, but require the user to specifically enable it. You can 1663 1.1 mrg optionally control which decimal floating point format is used (either 1664 1.1.1.14 mrg ‘<samp>bid</samp>’ or ‘<samp>dpd</samp>’). The ‘<samp>bid</samp>’ (binary integer decimal) 1665 1.1.1.14 mrg format is default on i386 and x86_64 systems, and the ‘<samp>dpd</samp>’ 1666 1.1 mrg (densely packed decimal) format is default on PowerPC systems. 1667 1.1.1.14 mrg </p> 1668 1.1.1.14 mrg </dd> 1669 1.1.1.20 mrg <dt><span><code>--enable-fixed-point</code></span></dt> 1670 1.1.1.20 mrg <dt><span><code>--disable-fixed-point</code></span></dt> 1671 1.1.1.14 mrg <dd><p>Enable (or disable) support for C fixed-point arithmetic. 1672 1.1 mrg This option is enabled by default for some targets (such as MIPS) which 1673 1.1 mrg have hardware-support for fixed-point operations. On other targets, you 1674 1.1 mrg may enable this option manually. 1675 1.1.1.14 mrg </p> 1676 1.1.1.14 mrg </dd> 1677 1.1.1.20 mrg <dt><span><code>--with-long-double-128</code></span></dt> 1678 1.1.1.14 mrg <dd><p>Specify if <code>long double</code> type should be 128-bit by default on selected 1679 1.1 mrg GNU/Linux architectures. If using <code>--without-long-double-128</code>, 1680 1.1.1.14 mrg <code>long double</code> will be by default 64-bit, the same as <code>double</code> type. 1681 1.1 mrg When neither of these configure options are used, the default will be 1682 1.1 mrg 128-bit <code>long double</code> when built against GNU C Library 2.4 and later, 1683 1.1 mrg 64-bit <code>long double</code> otherwise. 1684 1.1.1.14 mrg </p> 1685 1.1.1.14 mrg </dd> 1686 1.1.1.20 mrg <dt><span><code>--with-long-double-format=ibm</code></span></dt> 1687 1.1.1.20 mrg <dt><span><code>--with-long-double-format=ieee</code></span></dt> 1688 1.1.1.14 mrg <dd><p>Specify whether <code>long double</code> uses the IBM extended double format 1689 1.1.1.14 mrg or the IEEE 128-bit floating point format on PowerPC Linux systems. 1690 1.1.1.14 mrg This configuration switch will only work on little endian PowerPC 1691 1.1.1.14 mrg Linux systems and on big endian 64-bit systems where the default cpu 1692 1.1.1.14 mrg is at least power7 (i.e. <samp>--with-cpu=power7</samp>, 1693 1.1.1.14 mrg <samp>--with-cpu=power8</samp>, or <samp>--with-cpu=power9</samp> is used). 1694 1.1.1.14 mrg </p> 1695 1.1.1.14 mrg <p>If you use the <samp>--with-long-double-64</samp> configuration option, 1696 1.1.1.14 mrg the <samp>--with-long-double-format=ibm</samp> and 1697 1.1.1.14 mrg <samp>--with-long-double-format=ieee</samp> options are ignored. 1698 1.1.1.14 mrg </p> 1699 1.1.1.14 mrg <p>The default <code>long double</code> format is to use IBM extended double. 1700 1.1.1.14 mrg Until all of the libraries are converted to use IEEE 128-bit floating 1701 1.1.1.14 mrg point, it is not recommended to use 1702 1.1.1.14 mrg <samp>--with-long-double-format=ieee</samp>. 1703 1.1.1.14 mrg </p> 1704 1.1.1.14 mrg </dd> 1705 1.1.1.20 mrg <dt><span><code>--enable-fdpic</code></span></dt> 1706 1.1.1.14 mrg <dd><p>On SH Linux systems, generate ELF FDPIC code. 1707 1.1.1.14 mrg </p> 1708 1.1.1.14 mrg </dd> 1709 1.1.1.20 mrg <dt><span><code>--with-gmp=<var>pathname</var></code></span></dt> 1710 1.1.1.20 mrg <dt><span><code>--with-gmp-include=<var>pathname</var></code></span></dt> 1711 1.1.1.20 mrg <dt><span><code>--with-gmp-lib=<var>pathname</var></code></span></dt> 1712 1.1.1.20 mrg <dt><span><code>--with-mpfr=<var>pathname</var></code></span></dt> 1713 1.1.1.20 mrg <dt><span><code>--with-mpfr-include=<var>pathname</var></code></span></dt> 1714 1.1.1.20 mrg <dt><span><code>--with-mpfr-lib=<var>pathname</var></code></span></dt> 1715 1.1.1.20 mrg <dt><span><code>--with-mpc=<var>pathname</var></code></span></dt> 1716 1.1.1.20 mrg <dt><span><code>--with-mpc-include=<var>pathname</var></code></span></dt> 1717 1.1.1.20 mrg <dt><span><code>--with-mpc-lib=<var>pathname</var></code></span></dt> 1718 1.1.1.14 mrg <dd><p>If you want to build GCC but do not have the GMP library, the MPFR 1719 1.1 mrg library and/or the MPC library installed in a standard location and 1720 1.1.1.3 skrll do not have their sources present in the GCC source tree then you 1721 1.1.1.3 skrll can explicitly specify the directory where they are installed 1722 1.1.1.14 mrg (‘<samp>--with-gmp=<var>gmpinstalldir</var></samp>’, 1723 1.1.1.14 mrg ‘<samp>--with-mpfr=<var>mpfrinstalldir</var></samp>’, 1724 1.1.1.14 mrg ‘<samp>--with-mpc=<var>mpcinstalldir</var></samp>’). The 1725 1.1.1.14 mrg <samp>--with-gmp=<var>gmpinstalldir</var></samp> option is shorthand for 1726 1.1.1.14 mrg <samp>--with-gmp-lib=<var>gmpinstalldir</var>/lib</samp> and 1727 1.1.1.14 mrg <samp>--with-gmp-include=<var>gmpinstalldir</var>/include</samp>. Likewise the 1728 1.1.1.14 mrg <samp>--with-mpfr=<var>mpfrinstalldir</var></samp> option is shorthand for 1729 1.1.1.14 mrg <samp>--with-mpfr-lib=<var>mpfrinstalldir</var>/lib</samp> and 1730 1.1.1.14 mrg <samp>--with-mpfr-include=<var>mpfrinstalldir</var>/include</samp>, also the 1731 1.1.1.14 mrg <samp>--with-mpc=<var>mpcinstalldir</var></samp> option is shorthand for 1732 1.1.1.14 mrg <samp>--with-mpc-lib=<var>mpcinstalldir</var>/lib</samp> and 1733 1.1.1.14 mrg <samp>--with-mpc-include=<var>mpcinstalldir</var>/include</samp>. If these 1734 1.1 mrg shorthand assumptions are not correct, you can use the explicit 1735 1.1.1.3 skrll include and lib options directly. You might also need to ensure the 1736 1.1.1.3 skrll shared libraries can be found by the dynamic linker when building and 1737 1.1.1.3 skrll using GCC, for example by setting the runtime shared library path 1738 1.1.1.14 mrg variable (<code>LD_LIBRARY_PATH</code> on GNU/Linux and Solaris systems). 1739 1.1.1.14 mrg </p> 1740 1.1.1.14 mrg <p>These flags are applicable to the host platform only. When building 1741 1.1.1.3 skrll a cross compiler, they will not be used to configure target libraries. 1742 1.1.1.14 mrg </p> 1743 1.1.1.14 mrg </dd> 1744 1.1.1.20 mrg <dt><span><code>--with-isl=<var>pathname</var></code></span></dt> 1745 1.1.1.20 mrg <dt><span><code>--with-isl-include=<var>pathname</var></code></span></dt> 1746 1.1.1.20 mrg <dt><span><code>--with-isl-lib=<var>pathname</var></code></span></dt> 1747 1.1.1.14 mrg <dd><p>If you do not have the isl library installed in a standard location and you 1748 1.1.1.6 mrg want to build GCC, you can explicitly specify the directory where it is 1749 1.1.1.14 mrg installed (‘<samp>--with-isl=<var>islinstalldir</var></samp>’). The 1750 1.1.1.14 mrg <samp>--with-isl=<var>islinstalldir</var></samp> option is shorthand for 1751 1.1.1.14 mrg <samp>--with-isl-lib=<var>islinstalldir</var>/lib</samp> and 1752 1.1.1.14 mrg <samp>--with-isl-include=<var>islinstalldir</var>/include</samp>. If this 1753 1.1.1.6 mrg shorthand assumption is not correct, you can use the explicit 1754 1.1 mrg include and lib options directly. 1755 1.1.1.14 mrg </p> 1756 1.1.1.14 mrg <p>These flags are applicable to the host platform only. When building 1757 1.1.1.3 skrll a cross compiler, they will not be used to configure target libraries. 1758 1.1.1.14 mrg </p> 1759 1.1.1.14 mrg </dd> 1760 1.1.1.20 mrg <dt><span><code>--with-stage1-ldflags=<var>flags</var></code></span></dt> 1761 1.1.1.14 mrg <dd><p>This option may be used to set linker flags to be used when linking 1762 1.1 mrg stage 1 of GCC. These are also used when linking GCC if configured with 1763 1.1.1.14 mrg <samp>--disable-bootstrap</samp>. If <samp>--with-stage1-libs</samp> is not set to a 1764 1.1.1.14 mrg value, then the default is ‘<samp>-static-libstdc++ -static-libgcc</samp>’, if 1765 1.1.1.8 mrg supported. 1766 1.1.1.14 mrg </p> 1767 1.1.1.14 mrg </dd> 1768 1.1.1.20 mrg <dt><span><code>--with-stage1-libs=<var>libs</var></code></span></dt> 1769 1.1.1.14 mrg <dd><p>This option may be used to set libraries to be used when linking stage 1 1770 1.1 mrg of GCC. These are also used when linking GCC if configured with 1771 1.1.1.14 mrg <samp>--disable-bootstrap</samp>. 1772 1.1.1.14 mrg </p> 1773 1.1.1.14 mrg </dd> 1774 1.1.1.20 mrg <dt><span><code>--with-boot-ldflags=<var>flags</var></code></span></dt> 1775 1.1.1.14 mrg <dd><p>This option may be used to set linker flags to be used when linking 1776 1.1.1.8 mrg stage 2 and later when bootstrapping GCC. If –with-boot-libs 1777 1.1.1.8 mrg is not is set to a value, then the default is 1778 1.1.1.14 mrg ‘<samp>-static-libstdc++ -static-libgcc</samp>’. 1779 1.1.1.14 mrg </p> 1780 1.1.1.14 mrg </dd> 1781 1.1.1.20 mrg <dt><span><code>--with-boot-libs=<var>libs</var></code></span></dt> 1782 1.1.1.14 mrg <dd><p>This option may be used to set libraries to be used when linking stage 2 1783 1.1.1.8 mrg and later when bootstrapping GCC. 1784 1.1.1.14 mrg </p> 1785 1.1.1.14 mrg </dd> 1786 1.1.1.20 mrg <dt><span><code>--with-debug-prefix-map=<var>map</var></code></span></dt> 1787 1.1.1.14 mrg <dd><p>Convert source directory names using <samp>-fdebug-prefix-map</samp> when 1788 1.1 mrg building runtime libraries. ‘<samp><var>map</var></samp>’ is a space-separated 1789 1.1.1.14 mrg list of maps of the form ‘<samp><var>old</var>=<var>new</var></samp>’. 1790 1.1.1.14 mrg </p> 1791 1.1.1.14 mrg </dd> 1792 1.1.1.20 mrg <dt><span><code>--enable-linker-build-id</code></span></dt> 1793 1.1.1.14 mrg <dd><p>Tells GCC to pass <samp>--build-id</samp> option to the linker for all final 1794 1.1.1.14 mrg links (links performed without the <samp>-r</samp> or <samp>--relocatable</samp> 1795 1.1 mrg option), if the linker supports it. If you specify 1796 1.1.1.14 mrg <samp>--enable-linker-build-id</samp>, but your linker does not 1797 1.1.1.14 mrg support <samp>--build-id</samp> option, a warning is issued and the 1798 1.1.1.14 mrg <samp>--enable-linker-build-id</samp> option is ignored. The default is off. 1799 1.1.1.14 mrg </p> 1800 1.1.1.14 mrg </dd> 1801 1.1.1.20 mrg <dt><span><code>--with-linker-hash-style=<var>choice</var></code></span></dt> 1802 1.1.1.14 mrg <dd><p>Tells GCC to pass <samp>--hash-style=<var>choice</var></samp> option to the 1803 1.1.1.3 skrll linker for all final links. <var>choice</var> can be one of 1804 1.1.1.14 mrg ‘<samp>sysv</samp>’, ‘<samp>gnu</samp>’, and ‘<samp>both</samp>’ where ‘<samp>sysv</samp>’ is the default. 1805 1.1.1.14 mrg </p> 1806 1.1.1.14 mrg </dd> 1807 1.1.1.20 mrg <dt><span><code>--enable-gnu-unique-object</code></span></dt> 1808 1.1.1.20 mrg <dt><span><code>--disable-gnu-unique-object</code></span></dt> 1809 1.1.1.14 mrg <dd><p>Tells GCC to use the gnu_unique_object relocation for C++ template 1810 1.1 mrg static data members and inline function local statics. Enabled by 1811 1.1.1.6 mrg default for a toolchain with an assembler that accepts it and 1812 1.1 mrg GLIBC 2.11 or above, otherwise disabled. 1813 1.1.1.14 mrg </p> 1814 1.1.1.14 mrg </dd> 1815 1.1.1.20 mrg <dt><span><code>--with-diagnostics-color=<var>choice</var></code></span></dt> 1816 1.1.1.14 mrg <dd><p>Tells GCC to use <var>choice</var> as the default for <samp>-fdiagnostics-color=</samp> 1817 1.1.1.6 mrg option (if not used explicitly on the command line). <var>choice</var> 1818 1.1.1.14 mrg can be one of ‘<samp>never</samp>’, ‘<samp>auto</samp>’, ‘<samp>always</samp>’, and ‘<samp>auto-if-env</samp>’ 1819 1.1.1.16 mrg where ‘<samp>auto</samp>’ is the default. ‘<samp>auto-if-env</samp>’ makes 1820 1.1.1.16 mrg <samp>-fdiagnostics-color=auto</samp> the default if <code>GCC_COLORS</code> 1821 1.1.1.16 mrg is present and non-empty in the environment of the compiler, and 1822 1.1.1.14 mrg <samp>-fdiagnostics-color=never</samp> otherwise. 1823 1.1.1.14 mrg </p> 1824 1.1.1.14 mrg </dd> 1825 1.1.1.20 mrg <dt><span><code>--with-diagnostics-urls=<var>choice</var></code></span></dt> 1826 1.1.1.16 mrg <dd><p>Tells GCC to use <var>choice</var> as the default for <samp>-fdiagnostics-urls=</samp> 1827 1.1.1.16 mrg option (if not used explicitly on the command line). <var>choice</var> 1828 1.1.1.16 mrg can be one of ‘<samp>never</samp>’, ‘<samp>auto</samp>’, ‘<samp>always</samp>’, and ‘<samp>auto-if-env</samp>’ 1829 1.1.1.16 mrg where ‘<samp>auto</samp>’ is the default. ‘<samp>auto-if-env</samp>’ makes 1830 1.1.1.16 mrg <samp>-fdiagnostics-urls=auto</samp> the default if <code>GCC_URLS</code> 1831 1.1.1.16 mrg or <code>TERM_URLS</code> is present and non-empty in the environment of the 1832 1.1.1.16 mrg compiler, and <samp>-fdiagnostics-urls=never</samp> otherwise. 1833 1.1.1.16 mrg </p> 1834 1.1.1.16 mrg </dd> 1835 1.1.1.20 mrg <dt><span><code>--enable-lto</code></span></dt> 1836 1.1.1.20 mrg <dt><span><code>--disable-lto</code></span></dt> 1837 1.1.1.14 mrg <dd><p>Enable support for link-time optimization (LTO). This is enabled by 1838 1.1.1.14 mrg default, and may be disabled using <samp>--disable-lto</samp>. 1839 1.1.1.14 mrg </p> 1840 1.1.1.14 mrg </dd> 1841 1.1.1.20 mrg <dt><span><code>--enable-linker-plugin-configure-flags=FLAGS</code></span></dt> 1842 1.1.1.20 mrg <dt><span><code>--enable-linker-plugin-flags=FLAGS</code></span></dt> 1843 1.1.1.14 mrg <dd><p>By default, linker plugins (such as the LTO plugin) are built for the 1844 1.1.1.6 mrg host system architecture. For the case that the linker has a 1845 1.1.1.6 mrg different (but run-time compatible) architecture, these flags can be 1846 1.1.1.6 mrg specified to build plugins that are compatible to the linker. For 1847 1.1.1.6 mrg example, if you are building GCC for a 64-bit x86_64 1848 1.1.1.15 mrg (‘<samp>x86_64-pc-linux-gnu</samp>’) host system, but have a 32-bit x86 1849 1.1.1.14 mrg GNU/Linux (‘<samp>i686-pc-linux-gnu</samp>’) linker executable (which is 1850 1.1.1.6 mrg executable on the former system), you can configure GCC as follows for 1851 1.1.1.6 mrg getting compatible linker plugins: 1852 1.1.1.14 mrg </p> 1853 1.1.1.20 mrg <div class="example"> 1854 1.1.1.20 mrg <pre class="example">% <var>srcdir</var>/configure \ 1855 1.1.1.15 mrg --host=x86_64-pc-linux-gnu \ 1856 1.1.1.14 mrg --enable-linker-plugin-configure-flags=--host=i686-pc-linux-gnu \ 1857 1.1.1.14 mrg --enable-linker-plugin-flags='CC=gcc\ -m32\ -Wl,-rpath,[...]/i686-pc-linux-gnu/lib' 1858 1.1.1.14 mrg </pre></div> 1859 1.1.1.14 mrg 1860 1.1.1.14 mrg </dd> 1861 1.1.1.20 mrg <dt><span><code>--with-plugin-ld=<var>pathname</var></code></span></dt> 1862 1.1.1.14 mrg <dd><p>Enable an alternate linker to be used at link-time optimization (LTO) 1863 1.1.1.14 mrg link time when <samp>-fuse-linker-plugin</samp> is enabled. 1864 1.1.1.3 skrll This linker should have plugin support such as gold starting with 1865 1.1.1.14 mrg version 2.20 or GNU ld starting with version 2.21. 1866 1.1.1.14 mrg See <samp>-fuse-linker-plugin</samp> for details. 1867 1.1.1.14 mrg </p> 1868 1.1.1.14 mrg </dd> 1869 1.1.1.20 mrg <dt><span><code>--enable-canonical-system-headers</code></span></dt> 1870 1.1.1.20 mrg <dt><span><code>--disable-canonical-system-headers</code></span></dt> 1871 1.1.1.14 mrg <dd><p>Enable system header path canonicalization for <samp>libcpp</samp>. This can 1872 1.1.1.3 skrll produce shorter header file paths in diagnostics and dependency output 1873 1.1.1.3 skrll files, but these changed header paths may conflict with some compilation 1874 1.1.1.3 skrll environments. Enabled by default, and may be disabled using 1875 1.1.1.14 mrg <samp>--disable-canonical-system-headers</samp>. 1876 1.1.1.14 mrg </p> 1877 1.1.1.14 mrg </dd> 1878 1.1.1.20 mrg <dt><span><code>--with-glibc-version=<var>major</var>.<var>minor</var></code></span></dt> 1879 1.1.1.14 mrg <dd><p>Tell GCC that when the GNU C Library (glibc) is used on the target it 1880 1.1.1.6 mrg will be version <var>major</var>.<var>minor</var> or later. Normally this can 1881 1.1.1.14 mrg be detected from the C library’s header files, but this option may be 1882 1.1.1.6 mrg needed when bootstrapping a cross toolchain without the header files 1883 1.1.1.6 mrg available for building the initial bootstrap compiler. 1884 1.1.1.14 mrg </p> 1885 1.1.1.14 mrg <p>If GCC is configured with some multilibs that use glibc and some that 1886 1.1.1.14 mrg do not, this option applies only to the multilibs that use glibc. 1887 1.1.1.6 mrg However, such configurations may not work well as not all the relevant 1888 1.1.1.6 mrg configuration in GCC is on a per-multilib basis. 1889 1.1.1.14 mrg </p> 1890 1.1.1.14 mrg </dd> 1891 1.1.1.20 mrg <dt><span><code>--enable-as-accelerator-for=<var>target</var></code></span></dt> 1892 1.1.1.14 mrg <dd><p>Build as offload target compiler. Specify offload host triple by <var>target</var>. 1893 1.1.1.14 mrg </p> 1894 1.1.1.14 mrg </dd> 1895 1.1.1.20 mrg <dt><span><code>--enable-offload-targets=<var>target1</var>[=<var>path1</var>],…,<var>targetN</var>[=<var>pathN</var>]</code></span></dt> 1896 1.1.1.14 mrg <dd><p>Enable offloading to targets <var>target1</var>, …, <var>targetN</var>. 1897 1.1.1.6 mrg Offload compilers are expected to be already installed. Default search 1898 1.1.1.6 mrg path for them is <samp><var>exec-prefix</var></samp>, but it can be changed by 1899 1.1.1.14 mrg specifying paths <var>path1</var>, …, <var>pathN</var>. 1900 1.1.1.14 mrg </p> 1901 1.1.1.20 mrg <div class="example"> 1902 1.1.1.20 mrg <pre class="example">% <var>srcdir</var>/configure \ 1903 1.1.1.19 mrg --enable-offload-targets=x86_64-intelmicemul-linux-gnu=/path/to/x86_64/compiler,nvptx-none 1904 1.1.1.14 mrg </pre></div> 1905 1.1.1.8 mrg 1906 1.1.1.19 mrg </dd> 1907 1.1.1.20 mrg <dt><span><code>--enable-offload-defaulted</code></span></dt> 1908 1.1.1.19 mrg <dd> 1909 1.1.1.19 mrg <p>Tell GCC that configured but not installed offload compilers and libgomp 1910 1.1.1.19 mrg plugins are silently ignored. Useful for distribution compilers where 1911 1.1.1.19 mrg those are in separate optional packages and where the presence or absence 1912 1.1.1.19 mrg of those optional packages should determine the actual supported offloading 1913 1.1.1.19 mrg target set rather than the GCC configure-time selection. 1914 1.1.1.14 mrg </p> 1915 1.1.1.14 mrg </dd> 1916 1.1.1.20 mrg <dt><span><code>--with-hsa-runtime=<var>pathname</var></code></span></dt> 1917 1.1.1.20 mrg <dt><span><code>--with-hsa-runtime-include=<var>pathname</var></code></span></dt> 1918 1.1.1.20 mrg <dt><span><code>--with-hsa-runtime-lib=<var>pathname</var></code></span></dt> 1919 1.1.1.14 mrg <dd> 1920 1.1.1.19 mrg <p>If you configure GCC with offloading which uses an HSA run-time such as 1921 1.1.1.19 mrg AMDGCN but do not have the HSA run-time library installed in a standard 1922 1.1.1.19 mrg location then you can explicitly specify the directory where they are 1923 1.1.1.19 mrg installed. The <samp>--with-hsa-runtime=<var>hsainstalldir</var></samp> option 1924 1.1.1.19 mrg is a shorthand for 1925 1.1.1.14 mrg <samp>--with-hsa-runtime-lib=<var>hsainstalldir</var>/lib</samp> and 1926 1.1.1.14 mrg <samp>--with-hsa-runtime-include=<var>hsainstalldir</var>/include</samp>. 1927 1.1.1.14 mrg </p> 1928 1.1.1.14 mrg </dd> 1929 1.1.1.20 mrg <dt><span><code>--enable-cet</code></span></dt> 1930 1.1.1.20 mrg <dt><span><code>--disable-cet</code></span></dt> 1931 1.1.1.14 mrg <dd><p>Enable building target run-time libraries with control-flow 1932 1.1.1.14 mrg instrumentation, see <samp>-fcf-protection</samp> option. When 1933 1.1.1.14 mrg <code>--enable-cet</code> is specified target libraries are configured 1934 1.1.1.14 mrg to add <samp>-fcf-protection</samp> and, if needed, other target 1935 1.1.1.14 mrg specific options to a set of building options. 1936 1.1.1.14 mrg </p> 1937 1.1.1.19 mrg <p><code>--enable-cet=auto</code> is default. CET is enabled on Linux/x86 if 1938 1.1.1.19 mrg target binutils supports <code>Intel CET</code> instructions and disabled 1939 1.1.1.19 mrg otherwise. In this case, the target libraries are configured to get 1940 1.1.1.19 mrg additional <samp>-fcf-protection</samp> option. 1941 1.1.1.15 mrg </p> 1942 1.1.1.15 mrg </dd> 1943 1.1.1.20 mrg <dt><span><code>--with-riscv-attribute=‘<samp>yes</samp>’, ‘<samp>no</samp>’ or ‘<samp>default</samp>’</code></span></dt> 1944 1.1.1.15 mrg <dd><p>Generate RISC-V attribute by default, in order to record extra build 1945 1.1.1.15 mrg information in object. 1946 1.1.1.15 mrg </p> 1947 1.1.1.15 mrg <p>The option is disabled by default. It is enabled on RISC-V/ELF (bare-metal) 1948 1.1.1.15 mrg target if target binutils supported. 1949 1.1.1.19 mrg </p> 1950 1.1.1.19 mrg </dd> 1951 1.1.1.20 mrg <dt><span><code>--enable-s390-excess-float-precision</code></span></dt> 1952 1.1.1.20 mrg <dt><span><code>--disable-s390-excess-float-precision</code></span></dt> 1953 1.1.1.19 mrg <dd><p>On s390(x) targets, enable treatment of float expressions with double precision 1954 1.1.1.19 mrg when in standards-compliant mode (e.g., when <code>--std=c99</code> or 1955 1.1.1.19 mrg <code>-fexcess-precision=standard</code> are given). 1956 1.1.1.19 mrg </p> 1957 1.1.1.19 mrg <p>For a native build and cross compiles that have target headers, the option’s 1958 1.1.1.19 mrg default is derived from glibc’s behavior. When glibc clamps float_t to double, 1959 1.1.1.19 mrg GCC follows and enables the option. For other cross compiles, the default is 1960 1.1.1.19 mrg disabled. 1961 1.1.1.19 mrg </p> 1962 1.1.1.19 mrg </dd> 1963 1.1.1.20 mrg <dt><span><code>--with-zstd=<var>pathname</var></code></span></dt> 1964 1.1.1.20 mrg <dt><span><code>--with-zstd-include=<var>pathname</var></code></span></dt> 1965 1.1.1.20 mrg <dt><span><code>--with-zstd-lib=<var>pathname</var></code></span></dt> 1966 1.1.1.19 mrg <dd><p>If you do not have the <code>zstd</code> library installed in a standard 1967 1.1.1.19 mrg location and you want to build GCC, you can explicitly specify the 1968 1.1.1.19 mrg directory where it is installed (‘<samp>--with-zstd=<var>zstdinstalldir</var></samp>’). 1969 1.1.1.19 mrg The <samp>--with-zstd=<var>zstdinstalldir</var></samp> option is shorthand for 1970 1.1.1.19 mrg <samp>--with-zstd-lib=<var>zstdinstalldir</var>/lib</samp> and 1971 1.1.1.19 mrg <samp>--with-zstd-include=<var>zstdinstalldir</var>/include</samp>. If this 1972 1.1.1.19 mrg shorthand assumption is not correct, you can use the explicit 1973 1.1.1.19 mrg include and lib options directly. 1974 1.1.1.19 mrg </p> 1975 1.1.1.19 mrg <p>These flags are applicable to the host platform only. When building 1976 1.1.1.19 mrg a cross compiler, they will not be used to configure target libraries. 1977 1.1.1.14 mrg </p></dd> 1978 1.1.1.7 mrg </dl> 1979 1.1.1.5 mrg 1980 1.1.1.20 mrg <span id="Cross-Compiler-Specific-Options"></span><h4 class="subheading">Cross-Compiler-Specific Options</h4> 1981 1.1 mrg <p>The following options only apply to building cross compilers. 1982 1.1.1.14 mrg </p> 1983 1.1.1.14 mrg <dl compact="compact"> 1984 1.1.1.20 mrg <dt><span><code>--with-toolexeclibdir=<var>dir</var></code></span></dt> 1985 1.1.1.16 mrg <dd><p>Specify the installation directory for libraries built with a cross compiler. 1986 1.1.1.16 mrg The default is <samp>${gcc_tooldir}/lib</samp>. 1987 1.1.1.16 mrg </p> 1988 1.1.1.16 mrg </dd> 1989 1.1.1.20 mrg <dt><span><code>--with-sysroot</code></span></dt> 1990 1.1.1.20 mrg <dt><span><code>--with-sysroot=<var>dir</var></code></span></dt> 1991 1.1.1.14 mrg <dd><p>Tells GCC to consider <var>dir</var> as the root of a tree that contains 1992 1.1.1.14 mrg (a subset of) the root filesystem of the target operating system. 1993 1.1 mrg Target system headers, libraries and run-time object files will be 1994 1.1.1.3 skrll searched for in there. More specifically, this acts as if 1995 1.1.1.14 mrg <samp>--sysroot=<var>dir</var></samp> was added to the default options of the built 1996 1.1 mrg compiler. The specified directory is not copied into the 1997 1.1.1.14 mrg install tree, unlike the options <samp>--with-headers</samp> and 1998 1.1.1.14 mrg <samp>--with-libs</samp> that this option obsoletes. The default value, 1999 1.1.1.14 mrg in case <samp>--with-sysroot</samp> is not given an argument, is 2000 1.1.1.14 mrg <samp>${gcc_tooldir}/sys-root</samp>. If the specified directory is a 2001 1.1.1.14 mrg subdirectory of <samp>${exec_prefix}</samp>, then it will be found relative to 2002 1.1 mrg the GCC binaries if the installation tree is moved. 2003 1.1.1.14 mrg </p> 2004 1.1.1.14 mrg <p>This option affects the system root for the compiler used to build 2005 1.1 mrg target libraries (which runs on the build system) and the compiler newly 2006 1.1 mrg installed with <code>make install</code>; it does not affect the compiler which is 2007 1.1 mrg used to build GCC itself. 2008 1.1.1.14 mrg </p> 2009 1.1.1.14 mrg <p>If you specify the <samp>--with-native-system-header-dir=<var>dirname</var></samp> 2010 1.1.1.3 skrll option then the compiler will search that directory within <var>dirname</var> for 2011 1.1.1.14 mrg native system headers rather than the default <samp>/usr/include</samp>. 2012 1.1.1.14 mrg </p> 2013 1.1.1.14 mrg </dd> 2014 1.1.1.20 mrg <dt><span><code>--with-build-sysroot</code></span></dt> 2015 1.1.1.20 mrg <dt><span><code>--with-build-sysroot=<var>dir</var></code></span></dt> 2016 1.1.1.14 mrg <dd><p>Tells GCC to consider <var>dir</var> as the system root (see 2017 1.1.1.14 mrg <samp>--with-sysroot</samp>) while building target libraries, instead of 2018 1.1.1.14 mrg the directory specified with <samp>--with-sysroot</samp>. This option is 2019 1.1.1.14 mrg only useful when you are already using <samp>--with-sysroot</samp>. You 2020 1.1.1.14 mrg can use <samp>--with-build-sysroot</samp> when you are configuring with 2021 1.1.1.14 mrg <samp>--prefix</samp> set to a directory that is different from the one in 2022 1.1 mrg which you are installing GCC and your target libraries. 2023 1.1.1.14 mrg </p> 2024 1.1.1.14 mrg <p>This option affects the system root for the compiler used to build 2025 1.1 mrg target libraries (which runs on the build system); it does not affect 2026 1.1 mrg the compiler which is used to build GCC itself. 2027 1.1.1.14 mrg </p> 2028 1.1.1.14 mrg <p>If you specify the <samp>--with-native-system-header-dir=<var>dirname</var></samp> 2029 1.1.1.3 skrll option then the compiler will search that directory within <var>dirname</var> for 2030 1.1.1.14 mrg native system headers rather than the default <samp>/usr/include</samp>. 2031 1.1.1.14 mrg </p> 2032 1.1.1.14 mrg </dd> 2033 1.1.1.20 mrg <dt><span><code>--with-headers</code></span></dt> 2034 1.1.1.20 mrg <dt><span><code>--with-headers=<var>dir</var></code></span></dt> 2035 1.1.1.14 mrg <dd><p>Deprecated in favor of <samp>--with-sysroot</samp>. 2036 1.1.1.14 mrg Specifies that target headers are available when building a cross compiler. 2037 1.1 mrg The <var>dir</var> argument specifies a directory which has the target include 2038 1.1.1.14 mrg files. These include files will be copied into the <samp>gcc</samp> install 2039 1.1.1.14 mrg directory. <em>This option with the <var>dir</var> argument is required</em> when 2040 1.1.1.14 mrg building a cross compiler, if <samp><var>prefix</var>/<var>target</var>/sys-include</samp> 2041 1.1.1.14 mrg doesn’t pre-exist. If <samp><var>prefix</var>/<var>target</var>/sys-include</samp> does 2042 1.1.1.14 mrg pre-exist, the <var>dir</var> argument may be omitted. <code>fixincludes</code> 2043 1.1 mrg will be run on these files to make them compatible with GCC. 2044 1.1.1.14 mrg </p> 2045 1.1.1.14 mrg </dd> 2046 1.1.1.20 mrg <dt><span><code>--without-headers</code></span></dt> 2047 1.1.1.14 mrg <dd><p>Tells GCC not use any target headers from a libc when building a cross 2048 1.1 mrg compiler. When crossing to GNU/Linux, you need the headers so GCC 2049 1.1 mrg can build the exception handling for libgcc. 2050 1.1.1.14 mrg </p> 2051 1.1.1.14 mrg </dd> 2052 1.1.1.20 mrg <dt><span><code>--with-libs</code></span></dt> 2053 1.1.1.20 mrg <dt><span><code>--with-libs="<var>dir1</var> <var>dir2</var> … <var>dirN</var>"</code></span></dt> 2054 1.1.1.14 mrg <dd><p>Deprecated in favor of <samp>--with-sysroot</samp>. 2055 1.1 mrg Specifies a list of directories which contain the target runtime 2056 1.1.1.14 mrg libraries. These libraries will be copied into the <samp>gcc</samp> install 2057 1.1 mrg directory. If the directory list is omitted, this option has no 2058 1.1 mrg effect. 2059 1.1.1.14 mrg </p> 2060 1.1.1.14 mrg </dd> 2061 1.1.1.20 mrg <dt><span><code>--with-newlib</code></span></dt> 2062 1.1.1.14 mrg <dd><p>Specifies that ‘<samp>newlib</samp>’ is 2063 1.1 mrg being used as the target C library. This causes <code>__eprintf</code> to be 2064 1.1.1.14 mrg omitted from <samp>libgcc.a</samp> on the assumption that it will be provided by 2065 1.1.1.14 mrg ‘<samp>newlib</samp>’. 2066 1.1.1.14 mrg </p> 2067 1.1.1.16 mrg <a name="avr"></a> 2068 1.1.1.14 mrg </dd> 2069 1.1.1.20 mrg <dt><span><code>--with-avrlibc</code></span></dt> 2070 1.1.1.16 mrg <dd><p>Only supported for the AVR target. Specifies that ‘<samp>AVR-Libc</samp>’ is 2071 1.1.1.16 mrg being used as the target C library. This causes float support 2072 1.1.1.14 mrg functions like <code>__addsf3</code> to be omitted from <samp>libgcc.a</samp> on 2073 1.1.1.14 mrg the assumption that it will be provided by <samp>libm.a</samp>. For more 2074 1.1.1.19 mrg technical details, cf. <a href="https://gcc.gnu.org/PR54461">PR54461</a>. 2075 1.1.1.16 mrg It is not supported for 2076 1.1.1.3 skrll RTEMS configurations, which currently use newlib. The option is 2077 1.1.1.3 skrll supported since version 4.7.2 and is the default in 4.8.0 and newer. 2078 1.1.1.14 mrg </p> 2079 1.1.1.14 mrg </dd> 2080 1.1.1.20 mrg <dt><span><code>--with-double={32|64|32,64|64,32}</code></span></dt> 2081 1.1.1.20 mrg <dt><span><code>--with-long-double={32|64|32,64|64,32|double}</code></span></dt> 2082 1.1.1.16 mrg <dd><p>Only supported for the AVR target since version 10. 2083 1.1.1.16 mrg Specify the default layout available for the C/C++ ‘<samp>double</samp>’ 2084 1.1.1.16 mrg and ‘<samp>long double</samp>’ type, respectively. The following rules apply: 2085 1.1.1.16 mrg </p><ul> 2086 1.1.1.16 mrg <li> The first value after the ‘<samp>=</samp>’ specifies the default layout (in bits) 2087 1.1.1.16 mrg of the type and also the default for the <samp>-mdouble=</samp> resp. 2088 1.1.1.16 mrg <samp>-mlong-double=</samp> compiler option. 2089 1.1.1.16 mrg </li><li> If more than one value is specified, respective multilib variants are 2090 1.1.1.16 mrg available, and <samp>-mdouble=</samp> resp. <samp>-mlong-double=</samp> acts 2091 1.1.1.16 mrg as a multilib option. 2092 1.1.1.16 mrg </li><li> If <samp>--with-long-double=double</samp> is specified, ‘<samp>double</samp>’ and 2093 1.1.1.16 mrg ‘<samp>long double</samp>’ will have the same layout. 2094 1.1.1.16 mrg </li><li> The defaults are <samp>--with-long-double=64,32</samp> and 2095 1.1.1.16 mrg <samp>--with-double=32,64</samp>. The default ‘<samp>double</samp>’ layout imposed by 2096 1.1.1.16 mrg the latter is compatible with older versions of the compiler that implement 2097 1.1.1.16 mrg ‘<samp>double</samp>’ as a 32-bit type, which does not comply to the language standard. 2098 1.1.1.16 mrg </li></ul> 2099 1.1.1.16 mrg <p>Not all combinations of <samp>--with-double=</samp> and 2100 1.1.1.16 mrg <samp>--with-long-double=</samp> are valid. For example, the combination 2101 1.1.1.16 mrg <samp>--with-double=32,64</samp> <samp>--with-long-double=32</samp> will be 2102 1.1.1.16 mrg rejected because the first option specifies the availability of 2103 1.1.1.16 mrg multilibs for ‘<samp>double</samp>’, whereas the second option implies 2104 1.1.1.16 mrg that ‘<samp>long double</samp>’ — and hence also ‘<samp>double</samp>’ — is always 2105 1.1.1.16 mrg 32 bits wide. 2106 1.1.1.16 mrg </p> 2107 1.1.1.16 mrg </dd> 2108 1.1.1.20 mrg <dt><span><code>--with-double-comparison={tristate|bool|libf7}</code></span></dt> 2109 1.1.1.16 mrg <dd><p>Only supported for the AVR target since version 10. 2110 1.1.1.16 mrg Specify what result format is returned by library functions that 2111 1.1.1.16 mrg compare 64-bit floating point values (<code>DFmode</code>). 2112 1.1.1.16 mrg The GCC default is ‘<samp>tristate</samp>’. If the floating point 2113 1.1.1.16 mrg implementation returns a boolean instead, set it to ‘<samp>bool</samp>’. 2114 1.1.1.16 mrg </p> 2115 1.1.1.16 mrg </dd> 2116 1.1.1.20 mrg <dt><span><code>--with-libf7={libgcc|math|math-symbols|no}</code></span></dt> 2117 1.1.1.16 mrg <dd><p>Only supported for the AVR target since version 10. 2118 1.1.1.16 mrg Specify to which degree code from LibF7 is included in libgcc. 2119 1.1.1.16 mrg LibF7 is an ad-hoc, AVR-specific, 64-bit floating point emulation 2120 1.1.1.16 mrg written in C and (inline) assembly. ‘<samp>libgcc</samp>’ adds support 2121 1.1.1.16 mrg for functions that one would usually expect in libgcc like double addition, 2122 1.1.1.16 mrg double comparisons and double conversions. ‘<samp>math</samp>’ also adds routines 2123 1.1.1.16 mrg that one would expect in <samp>libm.a</samp>, but with <code>__</code> (two underscores) 2124 1.1.1.16 mrg prepended to the symbol names as specified by <samp>math.h</samp>. 2125 1.1.1.16 mrg ‘<samp>math-symbols</samp>’ also defines weak aliases for the functions 2126 1.1.1.16 mrg declared in <samp>math.h</samp>. However, <code>--with-libf7</code> won’t 2127 1.1.1.16 mrg install no <samp>math.h</samp> header file whatsoever, this file must come 2128 1.1.1.16 mrg from elsewhere. This option sets <samp>--with-double-comparison</samp> 2129 1.1.1.16 mrg to ‘<samp>bool</samp>’. 2130 1.1.1.16 mrg </p> 2131 1.1.1.16 mrg </dd> 2132 1.1.1.20 mrg <dt><span><code>--with-nds32-lib=<var>library</var></code></span></dt> 2133 1.1.1.14 mrg <dd><p>Specifies that <var>library</var> setting is used for building <samp>libgcc.a</samp>. 2134 1.1.1.14 mrg Currently, the valid <var>library</var> is ‘<samp>newlib</samp>’ or ‘<samp>mculib</samp>’. 2135 1.1.1.6 mrg This option is only supported for the NDS32 target. 2136 1.1.1.14 mrg </p> 2137 1.1.1.14 mrg </dd> 2138 1.1.1.20 mrg <dt><span><code>--with-build-time-tools=<var>dir</var></code></span></dt> 2139 1.1.1.14 mrg <dd><p>Specifies where to find the set of target tools (assembler, linker, etc.) 2140 1.1 mrg that will be used while building GCC itself. This option can be useful 2141 1.1 mrg if the directory layouts are different between the system you are building 2142 1.1 mrg GCC on, and the system where you will deploy it. 2143 1.1.1.14 mrg </p> 2144 1.1.1.14 mrg <p>For example, on an ‘<samp>ia64-hp-hpux</samp>’ system, you may have the GNU 2145 1.1.1.14 mrg assembler and linker in <samp>/usr/bin</samp>, and the native tools in a 2146 1.1 mrg different path, and build a toolchain that expects to find the 2147 1.1.1.14 mrg native tools in <samp>/usr/bin</samp>. 2148 1.1.1.14 mrg </p> 2149 1.1.1.14 mrg <p>When you use this option, you should ensure that <var>dir</var> includes 2150 1.1.1.14 mrg <code>ar</code>, <code>as</code>, <code>ld</code>, <code>nm</code>, 2151 1.1.1.14 mrg <code>ranlib</code> and <code>strip</code> if necessary, and possibly 2152 1.1.1.14 mrg <code>objdump</code>. Otherwise, GCC may use an inconsistent set of 2153 1.1.1.14 mrg tools. 2154 1.1.1.14 mrg </p></dd> 2155 1.1.1.7 mrg </dl> 2156 1.1.1.7 mrg 2157 1.1.1.20 mrg <span id="Overriding-configure-test-results"></span><h4 class="subsubheading">Overriding <code>configure</code> test results</h4> 2158 1.1.1.5 mrg 2159 1.1.1.7 mrg <p>Sometimes, it might be necessary to override the result of some 2160 1.1.1.14 mrg <code>configure</code> test, for example in order to ease porting to a new 2161 1.1.1.14 mrg system or work around a bug in a test. The toplevel <code>configure</code> 2162 1.1.1.7 mrg script provides three variables for this: 2163 1.1.1.14 mrg </p> 2164 1.1.1.14 mrg <dl compact="compact"> 2165 1.1.1.20 mrg <dt id='index-build_005fconfigargs'><span><code>build_configargs</code><a href='#index-build_005fconfigargs' class='copiable-anchor'> ¶</a></span></dt> 2166 1.1.1.20 mrg <dd><p>The contents of this variable is passed to all build <code>configure</code> 2167 1.1.1.7 mrg scripts. 2168 1.1.1.14 mrg </p> 2169 1.1.1.14 mrg </dd> 2170 1.1.1.20 mrg <dt id='index-host_005fconfigargs'><span><code>host_configargs</code><a href='#index-host_005fconfigargs' class='copiable-anchor'> ¶</a></span></dt> 2171 1.1.1.20 mrg <dd><p>The contents of this variable is passed to all host <code>configure</code> 2172 1.1.1.7 mrg scripts. 2173 1.1.1.14 mrg </p> 2174 1.1.1.14 mrg </dd> 2175 1.1.1.20 mrg <dt id='index-target_005fconfigargs'><span><code>target_configargs</code><a href='#index-target_005fconfigargs' class='copiable-anchor'> ¶</a></span></dt> 2176 1.1.1.20 mrg <dd><p>The contents of this variable is passed to all target <code>configure</code> 2177 1.1.1.7 mrg scripts. 2178 1.1.1.14 mrg </p> 2179 1.1.1.14 mrg </dd> 2180 1.1.1.14 mrg </dl> 2181 1.1 mrg 2182 1.1.1.14 mrg <p>In order to avoid shell and <code>make</code> quoting issues for complex 2183 1.1.1.14 mrg overrides, you can pass a setting for <code>CONFIG_SITE</code> and set 2184 1.1.1.7 mrg variables in the site file. 2185 1.1.1.14 mrg </p> 2186 1.1.1.20 mrg <span id="Objective-C-Specific-Options"></span><h4 class="subheading">Objective-C-Specific Options</h4> 2187 1.1.1.9 mrg 2188 1.1.1.10 mrg <p>The following options apply to the build of the Objective-C runtime library. 2189 1.1.1.14 mrg </p> 2190 1.1.1.14 mrg <dl compact="compact"> 2191 1.1.1.20 mrg <dt><span><code>--enable-objc-gc</code></span></dt> 2192 1.1.1.14 mrg <dd><p>Specify that an additional variant of the GNU Objective-C runtime library 2193 1.1.1.10 mrg is built, using an external build of the Boehm-Demers-Weiser garbage 2194 1.1.1.16 mrg collector (<a href="https://www.hboehm.info/gc/">https://www.hboehm.info/gc/</a>). This library needs to be 2195 1.1.1.10 mrg available for each multilib variant, unless configured with 2196 1.1.1.14 mrg <samp>--enable-objc-gc=‘<samp>auto</samp>’</samp> in which case the build of the 2197 1.1.1.10 mrg additional runtime library is skipped when not available and the build 2198 1.1.1.10 mrg continues. 2199 1.1.1.14 mrg </p> 2200 1.1.1.14 mrg </dd> 2201 1.1.1.20 mrg <dt><span><code>--with-target-bdw-gc=<var>list</var></code></span></dt> 2202 1.1.1.20 mrg <dt><span><code>--with-target-bdw-gc-include=<var>list</var></code></span></dt> 2203 1.1.1.20 mrg <dt><span><code>--with-target-bdw-gc-lib=<var>list</var></code></span></dt> 2204 1.1.1.14 mrg <dd><p>Specify search directories for the garbage collector header files and 2205 1.1.1.10 mrg libraries. <var>list</var> is a comma separated list of key value pairs of the 2206 1.1.1.14 mrg form ‘<samp><var>multilibdir</var>=<var>path</var></samp>’, where the default multilib key 2207 1.1.1.14 mrg is named as ‘<samp>.</samp>’ (dot), or is omitted (e.g. 2208 1.1.1.14 mrg ‘<samp>--with-target-bdw-gc=/opt/bdw-gc,32=/opt-bdw-gc32</samp>’). 2209 1.1.1.14 mrg </p> 2210 1.1.1.14 mrg <p>The options <samp>--with-target-bdw-gc-include</samp> and 2211 1.1.1.14 mrg <samp>--with-target-bdw-gc-lib</samp> must always be specified together 2212 1.1.1.10 mrg for each multilib variant and they take precedence over 2213 1.1.1.14 mrg <samp>--with-target-bdw-gc</samp>. If <samp>--with-target-bdw-gc-include</samp> 2214 1.1.1.10 mrg is missing values for a multilib, then the value for the default 2215 1.1.1.14 mrg multilib is used (e.g. ‘<samp>--with-target-bdw-gc-include=/opt/bdw-gc/include</samp>’ 2216 1.1.1.14 mrg ‘<samp>--with-target-bdw-gc-lib=/opt/bdw-gc/lib64,32=/opt-bdw-gc/lib32</samp>’). 2217 1.1.1.10 mrg If none of these options are specified, the library is assumed in 2218 1.1.1.14 mrg default locations. 2219 1.1.1.14 mrg </p></dd> 2220 1.1.1.9 mrg </dl> 2221 1.1.1.3 skrll 2222 1.1.1.20 mrg <span id="D-Specific-Options"></span><h4 class="subheading">D-Specific Options</h4> 2223 1.1.1.15 mrg 2224 1.1.1.15 mrg <p>The following options apply to the build of the D runtime library. 2225 1.1.1.15 mrg </p> 2226 1.1.1.15 mrg <dl compact="compact"> 2227 1.1.1.20 mrg <dt><span><code>--enable-libphobos-checking</code></span></dt> 2228 1.1.1.20 mrg <dt><span><code>--disable-libphobos-checking</code></span></dt> 2229 1.1.1.20 mrg <dt><span><code>--enable-libphobos-checking=<var>list</var></code></span></dt> 2230 1.1.1.16 mrg <dd><p>This option controls whether run-time checks and contracts are compiled into 2231 1.1.1.16 mrg the D runtime library. When the option is not specified, the library is built 2232 1.1.1.16 mrg with ‘<samp>release</samp>’ checking. When the option is specified without a 2233 1.1.1.16 mrg <var>list</var>, the result is the same as ‘<samp>--enable-libphobos-checking=yes</samp>’. 2234 1.1.1.16 mrg Likewise, ‘<samp>--disable-libphobos-checking</samp>’ is equivalent to 2235 1.1.1.16 mrg ‘<samp>--enable-libphobos-checking=no</samp>’. 2236 1.1.1.16 mrg </p> 2237 1.1.1.16 mrg <p>The categories of checks available in <var>list</var> are ‘<samp>yes</samp>’ (compiles 2238 1.1.1.16 mrg libphobos with <samp>-fno-release</samp>), ‘<samp>no</samp>’ (compiles libphobos with 2239 1.1.1.16 mrg <samp>-frelease</samp>), ‘<samp>all</samp>’ (same as ‘<samp>yes</samp>’), ‘<samp>none</samp>’ or 2240 1.1.1.16 mrg ‘<samp>release</samp>’ (same as ‘<samp>no</samp>’). 2241 1.1.1.16 mrg </p> 2242 1.1.1.16 mrg <p>Individual checks available in <var>list</var> are ‘<samp>assert</samp>’ (compiles libphobos 2243 1.1.1.16 mrg with an extra option <samp>-fassert</samp>). 2244 1.1.1.16 mrg </p> 2245 1.1.1.16 mrg </dd> 2246 1.1.1.20 mrg <dt><span><code>--with-libphobos-druntime-only</code></span></dt> 2247 1.1.1.20 mrg <dt><span><code>--with-libphobos-druntime-only=<var>choice</var></code></span></dt> 2248 1.1.1.16 mrg <dd><p>Specify whether to build only the core D runtime library (druntime), or both 2249 1.1.1.16 mrg the core and standard library (phobos) into libphobos. This is useful for 2250 1.1.1.16 mrg targets that have full support in druntime, but no or incomplete support 2251 1.1.1.16 mrg in phobos. <var>choice</var> can be one of ‘<samp>auto</samp>’, ‘<samp>yes</samp>’, and ‘<samp>no</samp>’ 2252 1.1.1.16 mrg where ‘<samp>auto</samp>’ is the default. 2253 1.1.1.16 mrg </p> 2254 1.1.1.16 mrg <p>When the option is not specified, the default choice ‘<samp>auto</samp>’ means that it 2255 1.1.1.16 mrg is inferred whether the target has support for the phobos standard library. 2256 1.1.1.16 mrg When the option is specified without a <var>choice</var>, the result is the same as 2257 1.1.1.16 mrg ‘<samp>--with-libphobos-druntime-only=yes</samp>’. 2258 1.1.1.16 mrg </p> 2259 1.1.1.16 mrg </dd> 2260 1.1.1.20 mrg <dt><span><code>--with-target-system-zlib</code></span></dt> 2261 1.1.1.15 mrg <dd><p>Use installed ‘<samp>zlib</samp>’ rather than that included with GCC. This needs 2262 1.1.1.15 mrg to be available for each multilib variant, unless configured with 2263 1.1.1.15 mrg <samp>--with-target-system-zlib=‘<samp>auto</samp>’</samp> in which case the GCC included 2264 1.1.1.15 mrg ‘<samp>zlib</samp>’ is only used when the system installed library is not available. 2265 1.1.1.15 mrg </p></dd> 2266 1.1.1.15 mrg </dl> 2267 1.1.1.15 mrg 2268 1.1.1.14 mrg <hr /> 2269 1.1.1.14 mrg <p> 2270 1.1.1.9 mrg <p><a href="./index.html">Return to the GCC Installation page</a> 2271 1.1.1.14 mrg </p> 2272 1.1.1.14 mrg 2273 1.1.1.14 mrg 2274 1.1.1.14 mrg 2275 1.1.1.14 mrg 2276 1.1.1.14 mrg 2277 1.1.1.14 mrg 2278 1.1.1.14 mrg 2279 1.1.1.14 mrg 2280 1.1.1.14 mrg 2281 1.1 mrg 2282 1.1.1.14 mrg </body> 2283 1.1.1.14 mrg </html> 2284
Indexes created Thu Jul 16 00:26:27 UTC 2026